21152515256625 has 128 divisors (see below), whose sum is σ = 37111594770432. Its totient is φ = 10678298400000.

The previous prime is 21152515256617. The next prime is 21152515256633. The reversal of 21152515256625 is 52665251525112.

It is an interprime number because it is at equal distance from previous prime (21152515256617) and next prime (21152515256633).

It is not a de Polignac number, because 21152515256625 - 2³ = 21152515256617 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1974835020 + ... + 1974845730.

It is an arithmetic number, because the mean of its divisors is an integer number (289934334144).

Almost surely, 2^{21152515256625} is an apocalyptic number.

21152515256625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21152515256625 is a deficient number, since it is larger than the sum of its proper divisors (15959079513807).

21152515256625 is a wasteful number, since it uses less digits than its factorization.

21152515256625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13120 (or 13110 counting only the distinct ones).

The product of its digits is 1800000, while the sum is 48.

The spelling of 21152515256625 in words is "twenty-one trillion, one hundred fifty-two billion, five hundred fifteen million, two hundred fifty-six thousand, six hundred twenty-five".