77867945 has 4 divisors (see below), whose sum is σ = 93441540. Its totient is φ = 62294352.

The previous prime is 77867941. The next prime is 77867957. The reversal of 77867945 is 54976877.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54976877 = 23 ⋅2390299.

It can be written as a sum of positive squares in 2 ways, for example, as 59274601 + 18593344 = 7699^2 + 4312^2 .

It is a cyclic number.

It is not a de Polignac number, because 77867945 - 2² = 77867941 is a prime.

It is not an unprimeable number, because it can be changed into a prime (77867941) 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, 7786790 + ... + 7786799.

It is an arithmetic number, because the mean of its divisors is an integer number (23360385).

Almost surely, 2^77867945 is an apocalyptic number.

It is an amenable number.

77867945 is a deficient number, since it is larger than the sum of its proper divisors (15573595).

77867945 is a wasteful number, since it uses less digits than its factorization.

77867945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15573594.

The product of its digits is 2963520, while the sum is 53.

The square root of 77867945 is about 8824.2815571581. The cubic root of 77867945 is about 427.0246097698.

The spelling of 77867945 in words is "seventy-seven million, eight hundred sixty-seven thousand, nine hundred forty-five".