21354132415 has 64 divisors (see below), whose sum is σ = 32365928448. Its totient is φ = 13138329600.

The previous prime is 21354132407. The next prime is 21354132419. The reversal of 21354132415 is 51423145312.

It is not a de Polignac number, because 21354132415 - 2³ = 21354132407 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21354132419) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 21547570 + ... + 21548560.

It is an arithmetic number, because the mean of its divisors is an integer number (505717632).

Almost surely, 2^21354132415 is an apocalyptic number.

21354132415 is a deficient number, since it is larger than the sum of its proper divisors (11011796033).

21354132415 is a wasteful number, since it uses less digits than its factorization.

21354132415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1688.

The product of its digits is 14400, while the sum is 31.

Adding to 21354132415 its reverse (51423145312), we get a palindrome (72777277727).

The spelling of 21354132415 in words is "twenty-one billion, three hundred fifty-four million, one hundred thirty-two thousand, four hundred fifteen".