19977156836 has 48 divisors (see below), whose sum is σ = 43039624320. Its totient is φ = 7900865280.

The previous prime is 19977156827. The next prime is 19977156839. The reversal of 19977156836 is 63865177991.

It is not an unprimeable number, because it can be changed into a prime (19977156839) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2157176 + ... + 2166416.

It is an arithmetic number, because the mean of its divisors is an integer number (896658840).

Almost surely, 2^19977156836 is an apocalyptic number.

It is an amenable number.

19977156836 is an abundant number, since it is smaller than the sum of its proper divisors (23062467484).

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

19977156836 is a wasteful number, since it uses less digits than its factorization.

19977156836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15204 (or 15202 counting only the distinct ones).

The product of its digits is 17146080, while the sum is 62.

The spelling of 19977156836 in words is "nineteen billion, nine hundred seventy-seven million, one hundred fifty-six thousand, eight hundred thirty-six".