21570245760 has 128 divisors (see below), whose sum is σ = 78577372800. Its totient is φ = 4930338816.

The previous prime is 21570245707. The next prime is 21570245761. The reversal of 21570245760 is 6754207512.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (21570245761) 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, 789025 + ... + 815904.

It is an arithmetic number, because the mean of its divisors is an integer number (613885725).

Almost surely, 2^21570245760 is an apocalyptic number.

21570245760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21570245760 is an abundant number, since it is smaller than the sum of its proper divisors (57007127040).

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

21570245760 is a wasteful number, since it uses less digits than its factorization.

21570245760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1604958 (or 1604946 counting only the distinct ones).

The product of its (nonzero) digits is 117600, while the sum is 39.

The spelling of 21570245760 in words is "twenty-one billion, five hundred seventy million, two hundred forty-five thousand, seven hundred sixty".