21570221670 has 32 divisors (see below), whose sum is σ = 51773538528. Its totient is φ = 5751502848.

The previous prime is 21570221657. The next prime is 21570221719. The reversal of 21570221670 is 7612207512.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 350662 + ... + 407558.

It is an arithmetic number, because the mean of its divisors is an integer number (1617923079).

Almost surely, 2^21570221670 is an apocalyptic number.

21570221670 is an abundant number, since it is smaller than the sum of its proper divisors (30203316858).

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

21570221670 is a wasteful number, since it uses less digits than its factorization.

21570221670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69544.

The product of its (nonzero) digits is 11760, while the sum is 33.

The spelling of 21570221670 in words is "twenty-one billion, five hundred seventy million, two hundred twenty-one thousand, six hundred seventy".