21512423234515 has 16 divisors (see below), whose sum is σ = 26158298152896. Its totient is φ = 16982200972800.

The previous prime is 21512423234441. The next prime is 21512423234563. The reversal of 21512423234515 is 51543232421512.

It is not a de Polignac number, because 21512423234515 - 2⁷ = 21512423234387 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74182146 + ... + 74471575.

It is an arithmetic number, because the mean of its divisors is an integer number (1634893634556).

Almost surely, 2^{21512423234515} is an apocalyptic number.

21512423234515 is a deficient number, since it is larger than the sum of its proper divisors (4645874918381).

21512423234515 is a wasteful number, since it uses less digits than its factorization.

21512423234515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148654110.

The product of its digits is 288000, while the sum is 40.

The spelling of 21512423234515 in words is "twenty-one trillion, five hundred twelve billion, four hundred twenty-three million, two hundred thirty-four thousand, five hundred fifteen".