21513462465 has 32 divisors (see below), whose sum is σ = 37576452096. Its totient is φ = 10423636160.

The previous prime is 21513462449. The next prime is 21513462499. The reversal of 21513462465 is 56426431512.

It is not a de Polignac number, because 21513462465 - 2⁴ = 21513462449 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 201514 + ... + 289196.

It is an arithmetic number, because the mean of its divisors is an integer number (1174264128).

Almost surely, 2^21513462465 is an apocalyptic number.

It is an amenable number.

21513462465 is a deficient number, since it is larger than the sum of its proper divisors (16062989631).

21513462465 is a wasteful number, since it uses less digits than its factorization.

21513462465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89189.

The product of its digits is 172800, while the sum is 39.

Adding to 21513462465 its reverse (56426431512), we get a palindrome (77939893977).

The spelling of 21513462465 in words is "twenty-one billion, five hundred thirteen million, four hundred sixty-two thousand, four hundred sixty-five".