10621640 has 16 divisors (see below), whose sum is σ = 23898780. Its totient is φ = 4248640.

The previous prime is 10621621. The next prime is 10621643. The reversal of 10621640 is 4612601.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 10588516 + 33124 = 3254^2 + 182^2 .

It is a super-2 number, since 2×10621640² = 225638472579200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (10621643) 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, 132731 + ... + 132810.

Almost surely, 2^10621640 is an apocalyptic number.

10621640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

10621640 is an abundant number, since it is smaller than the sum of its proper divisors (13277140).

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

10621640 is a wasteful number, since it uses less digits than its factorization.

10621640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265552 (or 265548 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 10621640 is about 3259.0857613754. The cubic root of 10621640 is about 219.8183072859.

The spelling of 10621640 in words is "ten million, six hundred twenty-one thousand, six hundred forty".