100557720 has 128 divisors (see below), whose sum is σ = 354974400. Its totient is φ = 25233408.

The previous prime is 100557661. The next prime is 100557727. The reversal of 100557720 is 27755001.

100557720 is a `hidden beast` number, since 100 + 557 + 7 + 2 + 0 = 666.

It is a super-2 number, since 2×100557720² = 20223710103196800, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100557727) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15622 + ... + 21098.

Almost surely, 2^100557720 is an apocalyptic number.

100557720 is a gapful number since it is divisible by the number (10) 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 100557720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (177487200).

100557720 is an abundant number, since it is smaller than the sum of its proper divisors (254416680).

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

100557720 is a wasteful number, since it uses less digits than its factorization.

100557720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5514 (or 5504 counting only the distinct ones).

The product of its (nonzero) digits is 2450, while the sum is 27.

The square root of 100557720 is about 10027.8472265985. The cubic root of 100557720 is about 465.0201864286.

The spelling of 100557720 in words is "one hundred million, five hundred fifty-seven thousand, seven hundred twenty".