2646640 has 20 divisors (see below), whose sum is σ = 6153624. Its totient is φ = 1058624.

The previous prime is 2646619. The next prime is 2646641. The reversal of 2646640 is 466462.

It is a tau number, because it is divible by the number of its divisors (20).

It is a nialpdrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 2646599 and 2646608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2646641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16462 + ... + 16621.

2^2646640 is an apocalyptic number.

2646640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2646640 is an abundant number, since it is smaller than the sum of its proper divisors (3506984).

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

2646640 is a wasteful number, since it uses less digits than its factorization.

2646640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33096 (or 33090 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 2646640 is about 1626.8497164766. The cubic root of 2646640 is about 138.3242393338.

The spelling of 2646640 in words is "two million, six hundred forty-six thousand, six hundred forty".