21137042016 has 72 divisors (see below), whose sum is σ = 62334725544. Its totient is φ = 7045678080.

The previous prime is 21137041979. The next prime is 21137042027. The reversal of 21137042016 is 61024073112.

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×21137042016² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

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 11 ways as a sum of consecutive naturals, for example, 1351345 + ... + 1366896.

It is an arithmetic number, because the mean of its divisors is an integer number (865760077).

Almost surely, 2^21137042016 is an apocalyptic number.

It is an amenable number.

21137042016 is an abundant number, since it is smaller than the sum of its proper divisors (41197683528).

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

21137042016 is an equidigital number, since it uses as much as digits as its factorization.

21137042016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2718266 (or 2718246 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The spelling of 21137042016 in words is "twenty-one billion, one hundred thirty-seven million, forty-two thousand, sixteen".