21512540553234 has 64 divisors (see below), whose sum is σ = 45406051891200. Its totient is φ = 6775965966528.

The previous prime is 21512540553233. The next prime is 21512540553241. The reversal of 21512540553234 is 43235504521512.

It is not an unprimeable number, because it can be changed into a prime (21512540553233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 277338384 + ... + 277415940.

It is an arithmetic number, because the mean of its divisors is an integer number (709469560800).

Almost surely, 2^{21512540553234} is an apocalyptic number.

21512540553234 is an abundant number, since it is smaller than the sum of its proper divisors (23893511337966).

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

21512540553234 is a wasteful number, since it uses less digits than its factorization.

21512540553234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83807.

The product of its (nonzero) digits is 720000, while the sum is 42.

The spelling of 21512540553234 in words is "twenty-one trillion, five hundred twelve billion, five hundred forty million, five hundred fifty-three thousand, two hundred thirty-four".