21670447320 has 64 divisors (see below), whose sum is σ = 72234828000. Its totient is φ = 5778785664.

The previous prime is 21670447319. The next prime is 21670447327. The reversal of 21670447320 is 2374407612.

21670447320 is a `hidden beast` number, since 2 + 167 + 0 + 4 + 473 + 20 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21670447327) 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, 10031535 + ... + 10033694.

Almost surely, 2^21670447320 is an apocalyptic number.

21670447320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21670447320 is an abundant number, since it is smaller than the sum of its proper divisors (50564380680).

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

21670447320 is a wasteful number, since it uses less digits than its factorization.

21670447320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20065249 (or 20065239 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 36.

The spelling of 21670447320 in words is "twenty-one billion, six hundred seventy million, four hundred forty-seven thousand, three hundred twenty".