100778644 has 12 divisors (see below), whose sum is σ = 182051968. Its totient is φ = 48763800.

The previous prime is 100778621. The next prime is 100778647. The reversal of 100778644 is 446877001.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 406242 + ... + 406489.

Almost surely, 2^100778644 is an apocalyptic number.

It is an amenable number.

100778644 is a deficient number, since it is larger than the sum of its proper divisors (81273324).

100778644 is a wasteful number, since it uses less digits than its factorization.

100778644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 812766 (or 812764 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 37.

The square root of 100778644 is about 10038.8567078129. The cubic root of 100778644 is about 465.3604851021.

It can be divided in two parts, 10077 and 8644, that added together give a triangular number (18721 = T₁₉₃).

The spelling of 100778644 in words is "one hundred million, seven hundred seventy-eight thousand, six hundred forty-four".