100005720 has 64 divisors (see below), whose sum is σ = 300676320. Its totient is φ = 26609664.

The previous prime is 100005673. The next prime is 100005727. The reversal of 100005720 is 27500001.

It is a happy number.

It is a super-2 number, since 2×100005720² = 20002288065436800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 100005720.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100005727) 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, 101872 + ... + 102848.

Almost surely, 2^100005720 is an apocalyptic number.

100005720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

100005720 is an abundant number, since it is smaller than the sum of its proper divisors (200670600).

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

100005720 is a wasteful number, since it uses less digits than its factorization.

100005720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1844 (or 1840 counting only the distinct ones).

The product of its (nonzero) digits is 70, while the sum is 15.

The square root of 100005720 is about 10000.2859959103. The cubic root of 100005720 is about 464.1677331553.

Adding to 100005720 its reverse (27500001), we get a palindrome (127505721).

The spelling of 100005720 in words is "one hundred million, five thousand, seven hundred twenty".