21285117060 has 24 divisors (see below), whose sum is σ = 59598327936. Its totient is φ = 5676031200.

The previous prime is 21285117047. The next prime is 21285117157. The reversal of 21285117060 is 6071158212.

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, 177375916 + ... + 177376035.

It is an arithmetic number, because the mean of its divisors is an integer number (2483263664).

Almost surely, 2^21285117060 is an apocalyptic number.

21285117060 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21285117060 is an abundant number, since it is smaller than the sum of its proper divisors (38313210876).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21285117060 is a wasteful number, since it uses less digits than its factorization.

21285117060 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354751963 (or 354751961 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 33.

The spelling of 21285117060 in words is "twenty-one billion, two hundred eighty-five million, one hundred seventeen thousand, sixty".