21512423235020 has 48 divisors (see below), whose sum is σ = 46137915992448. Its totient is φ = 8421769144320.

The previous prime is 21512423235019. The next prime is 21512423235139. The reversal of 21512423235020 is 2053232421512.

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 15 ways as a sum of consecutive naturals, for example, 107504660 + ... + 107704580.

It is an arithmetic number, because the mean of its divisors is an integer number (961206583176).

Almost surely, 2^{21512423235020} is an apocalyptic number.

21512423235020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21512423235020 is an abundant number, since it is smaller than the sum of its proper divisors (24625492757428).

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

21512423235020 is a wasteful number, since it uses less digits than its factorization.

21512423235020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314450 (or 314448 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 32.

Adding to 21512423235020 its reverse (2053232421512), we get a palindrome (23565655656532).

The spelling of 21512423235020 in words is "twenty-one trillion, five hundred twelve billion, four hundred twenty-three million, two hundred thirty-five thousand, twenty".