21513511191 has 8 divisors (see below), whose sum is σ = 28702649584. Its totient is φ = 14333356800.

The previous prime is 21513511189. The next prime is 21513511199. The reversal of 21513511191 is 19111531512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21513511191 - 2¹ = 21513511189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21513511199) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2240410 + ... + 2249991.

It is an arithmetic number, because the mean of its divisors is an integer number (3587831198).

Almost surely, 2^21513511191 is an apocalyptic number.

21513511191 is a deficient number, since it is larger than the sum of its proper divisors (7189138393).

21513511191 is a wasteful number, since it uses less digits than its factorization.

21513511191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4492001.

The product of its digits is 1350, while the sum is 30.

The spelling of 21513511191 in words is "twenty-one billion, five hundred thirteen million, five hundred eleven thousand, one hundred ninety-one".