10621855644 has 12 divisors (see below), whose sum is σ = 24784329864. Its totient is φ = 3540618544.

The previous prime is 10621855637. The next prime is 10621855649. The reversal of 10621855644 is 44655812601.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×10621855644² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 10621855596 and 10621855605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10621855649) 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, 442577307 + ... + 442577330.

It is an arithmetic number, because the mean of its divisors is an integer number (2065360822).

Almost surely, 2^10621855644 is an apocalyptic number.

It is an amenable number.

10621855644 is an abundant number, since it is smaller than the sum of its proper divisors (14162474220).

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

10621855644 is a wasteful number, since it uses less digits than its factorization.

10621855644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 885154644 (or 885154642 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 42.

The spelling of 10621855644 in words is "ten billion, six hundred twenty-one million, eight hundred fifty-five thousand, six hundred forty-four".