2657664 has 64 divisors (see below), whose sum is σ = 7854000. Its totient is φ = 884736.

The previous prime is 2657657. The next prime is 2657671. The reversal of 2657664 is 4667562.

2657664 is a `hidden beast` number, since 26 + 576 + 64 = 666.

It is an interprime number because it is at equal distance from previous prime (2657657) and next prime (2657671).

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a d-powerful number, because it can be written as 2²¹ + 6² + 5 + 7³ + 6⁷ + 6⁷ + 4⁴ .

It is a nialpdrome in base 12.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3072 + ... + 3840.

2^2657664 is an apocalyptic number.

2657664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2657664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3927000).

2657664 is an abundant number, since it is smaller than the sum of its proper divisors (5196336).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2657664 is an equidigital number, since it uses as much as digits as its factorization.

2657664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 792 (or 774 counting only the distinct ones).

The product of its digits is 60480, while the sum is 36.

The square root of 2657664 is about 1630.2343389832. The cubic root of 2657664 is about 138.5160264181.

It can be divided in two parts, 2657 and 664, that added together give a triangular number (3321 = T₈₁).

The spelling of 2657664 in words is "two million, six hundred fifty-seven thousand, six hundred sixty-four".