21154533213504 has 28 divisors (see below), whose sum is σ = 55971369127904. Its totient is φ = 7051511071104.

The previous prime is 21154533213433. The next prime is 21154533213529. The reversal of 21154533213504 is 40531233545112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55089930052 + ... + 55089930435.

Almost surely, 2^{21154533213504} is an apocalyptic number.

21154533213504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21154533213504 is an abundant number, since it is smaller than the sum of its proper divisors (34816835914400).

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

21154533213504 is a wasteful number, since it uses less digits than its factorization.

21154533213504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110179860502 (or 110179860492 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 39.

Adding to 21154533213504 its reverse (40531233545112), we get a palindrome (61685766758616).

The spelling of 21154533213504 in words is "twenty-one trillion, one hundred fifty-four billion, five hundred thirty-three million, two hundred thirteen thousand, five hundred four".