87192779 has 4 divisors (see below), whose sum is σ = 92321784. Its totient is φ = 82063776.

The previous prime is 87192769. The next prime is 87192797. The reversal of 87192779 is 97729178.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97729178 = 2 ⋅48864589.

It is a cyclic number.

It is not a de Polignac number, because 87192779 - 2¹² = 87188683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87192709) 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, 2564477 + ... + 2564510.

It is an arithmetic number, because the mean of its divisors is an integer number (23080446).

Almost surely, 2^87192779 is an apocalyptic number.

87192779 is a deficient number, since it is larger than the sum of its proper divisors (5129005).

87192779 is a wasteful number, since it uses less digits than its factorization.

87192779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5129004.

The product of its digits is 444528, while the sum is 50.

The square root of 87192779 is about 9337.7073738686. The cubic root of 87192779 is about 443.4318053759.

The spelling of 87192779 in words is "eighty-seven million, one hundred ninety-two thousand, seven hundred seventy-nine".