21000252015 has 12 divisors (see below), whose sum is σ = 36400436904. Its totient is φ = 11200134384.

The previous prime is 21000251989. The next prime is 21000252073. The reversal of 21000252015 is 51025200012.

It is not a de Polignac number, because 21000252015 - 2⁷ = 21000251887 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 233336089 + ... + 233336178.

It is an arithmetic number, because the mean of its divisors is an integer number (3033369742).

Almost surely, 2^21000252015 is an apocalyptic number.

21000252015 is a deficient number, since it is larger than the sum of its proper divisors (15400184889).

21000252015 is a wasteful number, since it uses less digits than its factorization.

21000252015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 466672278 (or 466672275 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

Adding to 21000252015 its reverse (51025200012), we get a palindrome (72025452027).

The spelling of 21000252015 in words is "twenty-one billion, two hundred fifty-two thousand, fifteen".