100778640 has 80 divisors (see below), whose sum is σ = 326014848. Its totient is φ = 25704448.

The previous prime is 100778621. The next prime is 100778647. The reversal of 100778640 is 46877001.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (100778647) 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, 3609 + ... + 14648.

Almost surely, 2^100778640 is an apocalyptic number.

100778640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

100778640 is an abundant number, since it is smaller than the sum of its proper divisors (225236208).

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

100778640 is a wasteful number, since it uses less digits than its factorization.

100778640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18296 (or 18290 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 33.

The square root of 100778640 is about 10038.8565085870. The cubic root of 100778640 is about 465.3604789452.

The spelling of 100778640 in words is "one hundred million, seven hundred seventy-eight thousand, six hundred forty".