21690867590 has 32 divisors (see below), whose sum is σ = 46969701120. Its totient is φ = 7045454304.

The previous prime is 21690867589. The next prime is 21690867593. The reversal of 21690867590 is 9576809612.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21690867593) 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, 8153132 + ... + 8155791.

It is an arithmetic number, because the mean of its divisors is an integer number (1467803160).

Almost surely, 2^21690867590 is an apocalyptic number.

21690867590 is an abundant number, since it is smaller than the sum of its proper divisors (25278833530).

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

21690867590 is a wasteful number, since it uses less digits than its factorization.

21690867590 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16308956.

The product of its (nonzero) digits is 1632960, while the sum is 53.

The spelling of 21690867590 in words is "twenty-one billion, six hundred ninety million, eight hundred sixty-seven thousand, five hundred ninety".