78920901 has 12 divisors (see below), whose sum is σ = 114412012. Its totient is φ = 52422336.

The previous prime is 78920879. The next prime is 78920903. The reversal of 78920901 is 10902987.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 25250625 + 53670276 = 5025^2 + 7326^2 .

It is not a de Polignac number, because 78920901 - 2⁶ = 78920837 is a prime.

It is a super-2 number, since 2×78920901² = 12457017229303602, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78920903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13336 + ... + 18321.

Almost surely, 2^78920901 is an apocalyptic number.

It is an amenable number.

78920901 is a deficient number, since it is larger than the sum of its proper divisors (35491111).

78920901 is a wasteful number, since it uses less digits than its factorization.

78920901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31940 (or 31937 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 78920901 is about 8883.7436365532. The cubic root of 78920901 is about 428.9407876286.

The spelling of 78920901 in words is "seventy-eight million, nine hundred twenty thousand, nine hundred one".