100531638 has 16 divisors (see below), whose sum is σ = 223403760. Its totient is φ = 33510528.

The previous prime is 100531633. The next prime is 100531699. The reversal of 100531638 is 836135001.

It is a super-2 number, since 2×100531638² = 20213220477926088, 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 (100531633) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 930795 + ... + 930902.

It is an arithmetic number, because the mean of its divisors is an integer number (13962735).

Almost surely, 2^100531638 is an apocalyptic number.

100531638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

100531638 is an abundant number, since it is smaller than the sum of its proper divisors (122872122).

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

100531638 is a wasteful number, since it uses less digits than its factorization.

100531638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1861708 (or 1861702 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 100531638 is about 10026.5466637322. The cubic root of 100531638 is about 464.9799783263.

Adding to 100531638 its reverse (836135001), we get a palindrome (936666639).

The spelling of 100531638 in words is "one hundred million, five hundred thirty-one thousand, six hundred thirty-eight".