20171138400 has 792 divisors, whose sum is σ = 85799602224. Its totient is φ = 4534963200.

The previous prime is 20171138399. The next prime is 20171138443. The reversal of 20171138400 is 483117102.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 131 ways as a sum of consecutive naturals, for example, 330674370 + ... + 330674430.

Almost surely, 2^20171138400 is an apocalyptic number.

20171138400 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 20171138400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42899801112).

20171138400 is an abundant number, since it is smaller than the sum of its proper divisors (65628463824).

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

20171138400 is an frugal number, since it uses more digits than its factorization.

20171138400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118 (or 78 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The spelling of 20171138400 in words is "twenty billion, one hundred seventy-one million, one hundred thirty-eight thousand, four hundred".