79720245 has 42 divisors (see below), whose sum is σ = 151999926. Its totient is φ = 38652240.

The previous prime is 79720241. The next prime is 79720247. The reversal of 79720245 is 54202797.

It can be written as a sum of positive squares in only one way, i.e., 63776196 + 15944049 = 7986^2 + 3993^2 .

It is not a de Polignac number, because 79720245 - 2² = 79720241 is a prime.

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79720241) 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 41 ways as a sum of consecutive naturals, for example, 7247290 + ... + 7247300.

Almost surely, 2^79720245 is an apocalyptic number.

It is an amenable number.

79720245 is a deficient number, since it is larger than the sum of its proper divisors (72279681).

79720245 is an frugal number, since it uses more digits than its factorization.

79720245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77 (or 19 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The square root of 79720245 is about 8928.6194341567. The cubic root of 79720245 is about 430.3840898433.

Multiplying 79720245 by its product of nonzero digits (35280), we get a square (2812530243600 = 1677060²).

The spelling of 79720245 in words is "seventy-nine million, seven hundred twenty thousand, two hundred forty-five".