100778845 has 4 divisors (see below), whose sum is σ = 120934620. Its totient is φ = 80623072.

The previous prime is 100778837. The next prime is 100778851. The reversal of 100778845 is 548877001.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 64850809 + 35928036 = 8053^2 + 5994^2 .

It is a cyclic number.

It is not a de Polignac number, because 100778845 - 2³ = 100778837 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 100778798 and 100778807.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10077880 + ... + 10077889.

It is an arithmetic number, because the mean of its divisors is an integer number (30233655).

Almost surely, 2^100778845 is an apocalyptic number.

It is an amenable number.

100778845 is a deficient number, since it is larger than the sum of its proper divisors (20155775).

100778845 is an equidigital number, since it uses as much as digits as its factorization.

100778845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20155774.

The product of its (nonzero) digits is 62720, while the sum is 40.

The square root of 100778845 is about 10038.8667189081. The cubic root of 100778845 is about 465.3607944844.

The spelling of 100778845 in words is "one hundred million, seven hundred seventy-eight thousand, eight hundred forty-five".