21512114467 has 4 divisors (see below), whose sum is σ = 21524777800. Its totient is φ = 21499451136.

The previous prime is 21512114447. The next prime is 21512114471. The reversal of 21512114467 is 76441121512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21512114467 - 2⁷ = 21512114339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21512114447) 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 3 ways as a sum of consecutive naturals, for example, 6329118 + ... + 6332515.

It is an arithmetic number, because the mean of its divisors is an integer number (5381194450).

Almost surely, 2^21512114467 is an apocalyptic number.

21512114467 is a deficient number, since it is larger than the sum of its proper divisors (12663333).

21512114467 is a wasteful number, since it uses less digits than its factorization.

21512114467 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12663332.

The product of its digits is 13440, while the sum is 34.

Adding to 21512114467 its reverse (76441121512), we get a palindrome (97953235979).

The spelling of 21512114467 in words is "twenty-one billion, five hundred twelve million, one hundred fourteen thousand, four hundred sixty-seven".