77195981 has 4 divisors (see below), whose sum is σ = 80552352. Its totient is φ = 73839612.

The previous prime is 77195977. The next prime is 77196011. The reversal of 77195981 is 18959177.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 77195981 - 2² = 77195977 is a prime.

It is a super-2 number, since 2×77195981² = 11918438965104722, 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 (77195971) 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, 1678151 + ... + 1678196.

It is an arithmetic number, because the mean of its divisors is an integer number (20138088).

Almost surely, 2^77195981 is an apocalyptic number.

It is an amenable number.

77195981 is a deficient number, since it is larger than the sum of its proper divisors (3356371).

77195981 is a wasteful number, since it uses less digits than its factorization.

77195981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3356370.

The product of its digits is 158760, while the sum is 47.

The square root of 77195981 is about 8786.1243446698. The cubic root of 77195981 is about 425.7927184105.

The spelling of 77195981 in words is "seventy-seven million, one hundred ninety-five thousand, nine hundred eighty-one".