21356757502 has 32 divisors (see below), whose sum is σ = 33866864640. Its totient is φ = 10080766080.

The previous prime is 21356757481. The next prime is 21356757503. The reversal of 21356757502 is 20575765312.

It is a super-2 number, since 2×21356757502² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21356757503) 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, 1233727 + ... + 1250917.

It is an arithmetic number, because the mean of its divisors is an integer number (1058339520).

Almost surely, 2^21356757502 is an apocalyptic number.

21356757502 is a deficient number, since it is larger than the sum of its proper divisors (12510107138).

21356757502 is a wasteful number, since it uses less digits than its factorization.

21356757502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17568.

The product of its (nonzero) digits is 441000, while the sum is 43.

The spelling of 21356757502 in words is "twenty-one billion, three hundred fifty-six million, seven hundred fifty-seven thousand, five hundred two".