21513353454 has 12 divisors (see below), whose sum is σ = 46612265856. Its totient is φ = 7171117812.

The previous prime is 21513353447. The next prime is 21513353501. The reversal of 21513353454 is 45435331512.

21513353454 is a `hidden beast` number, since 2 + 151 + 3 + 3 + 53 + 454 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 597593134 + ... + 597593169.

It is an arithmetic number, because the mean of its divisors is an integer number (3884355488).

Almost surely, 2^21513353454 is an apocalyptic number.

21513353454 is an abundant number, since it is smaller than the sum of its proper divisors (25098912402).

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

21513353454 is a wasteful number, since it uses less digits than its factorization.

21513353454 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1195186311 (or 1195186308 counting only the distinct ones).

The product of its digits is 108000, while the sum is 36.

Adding to 21513353454 its reverse (45435331512), we get a palindrome (66948684966).

The spelling of 21513353454 in words is "twenty-one billion, five hundred thirteen million, three hundred fifty-three thousand, four hundred fifty-four".