21519373455 has 12 divisors (see below), whose sum is σ = 37300247400. Its totient is φ = 11476999152.

The previous prime is 21519373409. The next prime is 21519373471. The reversal of 21519373455 is 55437391512.

21519373455 is a `hidden beast` number, since 2 + 1 + 5 + 193 + 7 + 3 + 455 = 666.

It is not a de Polignac number, because 21519373455 - 2⁷ = 21519373327 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 478208299 = 21519373455 / (2 + 1 + 5 + 1 + 9 + 3 + 7 + 3 + 4 + 5 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 21519373455.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 239104105 + ... + 239104194.

It is an arithmetic number, because the mean of its divisors is an integer number (3108353950).

Almost surely, 2^21519373455 is an apocalyptic number.

21519373455 is a deficient number, since it is larger than the sum of its proper divisors (15780873945).

21519373455 is a wasteful number, since it uses less digits than its factorization.

21519373455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478208310 (or 478208307 counting only the distinct ones).

The product of its digits is 567000, while the sum is 45.

The spelling of 21519373455 in words is "twenty-one billion, five hundred nineteen million, three hundred seventy-three thousand, four hundred fifty-five".