21125542115 has 8 divisors (see below), whose sum is σ = 25442170800. Its totient is φ = 16839420192.

The previous prime is 21125542073. The next prime is 21125542129. The reversal of 21125542115 is 51124552112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21125542115 - 2¹⁰ = 21125541091 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7625165 + ... + 7627934.

It is an arithmetic number, because the mean of its divisors is an integer number (3180271350).

Almost surely, 2^21125542115 is an apocalyptic number.

21125542115 is a deficient number, since it is larger than the sum of its proper divisors (4316628685).

21125542115 is a wasteful number, since it uses less digits than its factorization.

21125542115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15253381.

The product of its digits is 4000, while the sum is 29.

The spelling of 21125542115 in words is "twenty-one billion, one hundred twenty-five million, five hundred forty-two thousand, one hundred fifteen".