21512045625464 has 32 divisors (see below), whose sum is σ = 42782091580800. Its totient is φ = 10112130718560.

The previous prime is 21512045625457. The next prime is 21512045625479. The reversal of 21512045625464 is 46452654021512.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 540158012 + ... + 540197835.

It is an arithmetic number, because the mean of its divisors is an integer number (1336940361900).

Almost surely, 2^{21512045625464} is an apocalyptic number.

It is an amenable number.

21512045625464 is a deficient number, since it is larger than the sum of its proper divisors (21270045955336).

21512045625464 is a wasteful number, since it uses less digits than its factorization.

21512045625464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1080356003 (or 1080355999 counting only the distinct ones).

The product of its (nonzero) digits is 2304000, while the sum is 47.

Adding to 21512045625464 its reverse (46452654021512), we get a palindrome (67964699646976).

The spelling of 21512045625464 in words is "twenty-one trillion, five hundred twelve billion, forty-five million, six hundred twenty-five thousand, four hundred sixty-four".