20311171800 has 96 divisors (see below), whose sum is σ = 63145698000. Its totient is φ = 5400737280.

The previous prime is 20311171799. The next prime is 20311171807. The reversal of 20311171800 is 817111302.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20311171807) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 160902 + ... + 257898.

Almost surely, 2^20311171800 is an apocalyptic number.

20311171800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20311171800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31572849000).

20311171800 is an abundant number, since it is smaller than the sum of its proper divisors (42834526200).

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

20311171800 is a wasteful number, since it uses less digits than its factorization.

20311171800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97365 (or 97356 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 24.

It can be divided in two parts, 203111 and 71800, that added together give a triangular number (274911 = T₇₄₁).

The spelling of 20311171800 in words is "twenty billion, three hundred eleven million, one hundred seventy-one thousand, eight hundred".