79431787 has 4 divisors (see below), whose sum is σ = 79875720. Its totient is φ = 78987856.

The previous prime is 79431763. The next prime is 79431791. The reversal of 79431787 is 78713497.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78713497 = 1279 ⋅61543.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79431787 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79431727) 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, 221698 + ... + 222055.

It is an arithmetic number, because the mean of its divisors is an integer number (19968930).

Almost surely, 2^79431787 is an apocalyptic number.

79431787 is a deficient number, since it is larger than the sum of its proper divisors (443933).

79431787 is a wasteful number, since it uses less digits than its factorization.

79431787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 443932.

The product of its digits is 296352, while the sum is 46.

The square root of 79431787 is about 8912.4512340882. The cubic root of 79431787 is about 429.8643650091.

It can be divided in two parts, 7943 and 1787, that added together give a triangular number (9730 = T₁₃₉).

The spelling of 79431787 in words is "seventy-nine million, four hundred thirty-one thousand, seven hundred eighty-seven".