21135026465 has 16 divisors (see below), whose sum is σ = 29012860800. Its totient is φ = 14478748800.

The previous prime is 21135026453. The next prime is 21135026477. The reversal of 21135026465 is 56462053112.

It is an interprime number because it is at equal distance from previous prime (21135026453) and next prime (21135026477).

It is not a de Polignac number, because 21135026465 - 2¹⁴ = 21135010081 is a prime.

It is a super-3 number, since 3×21135026465³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 251111 + ... + 324540.

It is an arithmetic number, because the mean of its divisors is an integer number (1813303800).

Almost surely, 2^21135026465 is an apocalyptic number.

It is an amenable number.

21135026465 is a deficient number, since it is larger than the sum of its proper divisors (7877834335).

21135026465 is a wasteful number, since it uses less digits than its factorization.

21135026465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 576712.

The product of its (nonzero) digits is 43200, while the sum is 35.

Adding to 21135026465 its reverse (56462053112), we get a palindrome (77597079577).

The spelling of 21135026465 in words is "twenty-one billion, one hundred thirty-five million, twenty-six thousand, four hundred sixty-five".