21357653410215 has 24 divisors (see below), whose sum is σ = 37020522247488. Its totient is φ = 11390567048640.

The previous prime is 21357653410141. The next prime is 21357653410217. The reversal of 21357653410215 is 51201435675312.

21357653410215 is a `hidden beast` number, since 2 + 1 + 3 + 5 + 7 + 6 + 534 + 102 + 1 + 5 = 666.

It is not a de Polignac number, because 21357653410215 - 2¹⁷ = 21357653279143 is a prime.

It is a super-2 number, since 2×21357653410215² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21357653410217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 899284 + ... + 6597273.

It is an arithmetic number, because the mean of its divisors is an integer number (1542521760312).

Almost surely, 2^{21357653410215} is an apocalyptic number.

21357653410215 is a deficient number, since it is larger than the sum of its proper divisors (15662868837273).

21357653410215 is a wasteful number, since it uses less digits than its factorization.

21357653410215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7559879 (or 7559876 counting only the distinct ones).

The product of its (nonzero) digits is 756000, while the sum is 45.

The spelling of 21357653410215 in words is "twenty-one trillion, three hundred fifty-seven billion, six hundred fifty-three million, four hundred ten thousand, two hundred fifteen".