2015656820 has 24 divisors (see below), whose sum is σ = 4331320224. Its totient is φ = 787512096.

The previous prime is 2015656813. The next prime is 2015656849. The reversal of 2015656820 is 286565102.

It is a congruent number.

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, 1171034 + ... + 1172753.

It is an arithmetic number, because the mean of its divisors is an integer number (180471676).

Almost surely, 2^2015656820 is an apocalyptic number.

2015656820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2015656820 is an abundant number, since it is smaller than the sum of its proper divisors (2315663404).

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

2015656820 is a wasteful number, since it uses less digits than its factorization.

2015656820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2343839 (or 2343837 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 35.

The square root of 2015656820 is about 44896.0668655953. The cubic root of 2015656820 is about 1263.2002339725.

The spelling of 2015656820 in words is "two billion, fifteen million, six hundred fifty-six thousand, eight hundred twenty".