21692425640 has 16 divisors (see below), whose sum is σ = 48807957780. Its totient is φ = 8676970240.

The previous prime is 21692425631. The next prime is 21692425679. The reversal of 21692425640 is 4652429612.

It can be written as a sum of positive squares in 2 ways, for example, as 18120928996 + 3571496644 = 134614^2 + 59762^2 .

It is a super-2 number, since 2×21692425640² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 271155281 + ... + 271155360.

Almost surely, 2^21692425640 is an apocalyptic number.

21692425640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21692425640 is an abundant number, since it is smaller than the sum of its proper divisors (27115532140).

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

21692425640 is a wasteful number, since it uses less digits than its factorization.

21692425640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 542310652 (or 542310648 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 41.

The spelling of 21692425640 in words is "twenty-one billion, six hundred ninety-two million, four hundred twenty-five thousand, six hundred forty".