2651640 has 64 divisors (see below), whose sum is σ = 8380800. Its totient is φ = 669312.

The previous prime is 2651639. The next prime is 2651651. The reversal of 2651640 is 461562.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 2651640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1699 + ... + 2861.

It is an arithmetic number, because the mean of its divisors is an integer number (130950).

2^2651640 is an apocalyptic number.

2651640 is a gapful number since it is divisible by the number (20) 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 2651640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4190400).

2651640 is an abundant number, since it is smaller than the sum of its proper divisors (5729160).

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

2651640 is a wasteful number, since it uses less digits than its factorization.

2651640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1196 (or 1192 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 2651640 is about 1628.3857036955. The cubic root of 2651640 is about 138.4112913594.

The spelling of 2651640 in words is "two million, six hundred fifty-one thousand, six hundred forty".