21640400864192 has 112 divisors (see below), whose sum is σ = 48827226200064. Its totient is φ = 9426817152000.

The previous prime is 21640400864171. The next prime is 21640400864197. The reversal of 21640400864192 is 29146800404612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21640400864197) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2565659 + ... + 7061402.

Almost surely, 2^{21640400864192} is an apocalyptic number.

21640400864192 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21640400864192 is an abundant number, since it is smaller than the sum of its proper divisors (27186825335872).

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

21640400864192 is a wasteful number, since it uses less digits than its factorization.

21640400864192 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9627218 (or 9627208 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 47.

The spelling of 21640400864192 in words is "twenty-one trillion, six hundred forty billion, four hundred million, eight hundred sixty-four thousand, one hundred ninety-two".