21670089920 has 56 divisors (see below), whose sum is σ = 53381300400. Its totient is φ = 8369134592.

The previous prime is 21670089871. The next prime is 21670089923. The reversal of 21670089920 is 2998007612.

It is a happy number.

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21670089923) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1158290 + ... + 1176849.

Almost surely, 2^21670089920 is an apocalyptic number.

21670089920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21670089920 is an abundant number, since it is smaller than the sum of its proper divisors (31711210480).

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

21670089920 is a wasteful number, since it uses less digits than its factorization.

21670089920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2335185 (or 2335175 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 44.

The spelling of 21670089920 in words is "twenty-one billion, six hundred seventy million, eighty-nine thousand, nine hundred twenty".