21054815345 has 16 divisors (see below), whose sum is σ = 25680188160. Its totient is φ = 16568664000.

The previous prime is 21054815297. The next prime is 21054815347. The reversal of 21054815345 is 54351845012.

It is not a de Polignac number, because 21054815345 - 2¹⁶ = 21054749809 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21054815299 and 21054815308.

It is not an unprimeable number, because it can be changed into a prime (21054815347) 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, 88295 + ... + 223395.

It is an arithmetic number, because the mean of its divisors is an integer number (1605011760).

Almost surely, 2^21054815345 is an apocalyptic number.

It is an amenable number.

21054815345 is a deficient number, since it is larger than the sum of its proper divisors (4625372815).

21054815345 is a wasteful number, since it uses less digits than its factorization.

21054815345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135616.

The product of its (nonzero) digits is 96000, while the sum is 38.

The spelling of 21054815345 in words is "twenty-one billion, fifty-four million, eight hundred fifteen thousand, three hundred forty-five".