21512245311 has 6 divisors (see below), whose sum is σ = 31073243240. Its totient is φ = 14341496868.

The previous prime is 21512245291. The next prime is 21512245331. The reversal of 21512245311 is 11354221512.

It is a happy number.

21512245311 is a `hidden beast` number, since 2 + 1 + 5 + 122 + 4 + 531 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (21512245291) and next prime (21512245331).

It is not a de Polignac number, because 21512245311 - 2²⁵ = 21478690879 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 (21512245331) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1195124731 + ... + 1195124748.

Almost surely, 2^21512245311 is an apocalyptic number.

21512245311 is a deficient number, since it is larger than the sum of its proper divisors (9560997929).

21512245311 is a wasteful number, since it uses less digits than its factorization.

21512245311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2390249485 (or 2390249482 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

Adding to 21512245311 its reverse (11354221512), we get a palindrome (32866466823).

The spelling of 21512245311 in words is "twenty-one billion, five hundred twelve million, two hundred forty-five thousand, three hundred eleven".