77540431 has 4 divisors (see below), whose sum is σ = 79003512. Its totient is φ = 76077352.

The previous prime is 77540423. The next prime is 77540447. The reversal of 77540431 is 13404577.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13404577 = 227 ⋅59051.

It is a cyclic number.

It is not a de Polignac number, because 77540431 - 2³ = 77540423 is a prime.

It is a super-2 number, since 2×77540431² = 12025036879331522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77540393 and 77540402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77540401) 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, 731461 + ... + 731566.

It is an arithmetic number, because the mean of its divisors is an integer number (19750878).

Almost surely, 2^77540431 is an apocalyptic number.

77540431 is a deficient number, since it is larger than the sum of its proper divisors (1463081).

77540431 is a wasteful number, since it uses less digits than its factorization.

77540431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1463080.

The product of its (nonzero) digits is 11760, while the sum is 31.

The square root of 77540431 is about 8805.7044579068. The cubic root of 77540431 is about 426.4250773297.

The spelling of 77540431 in words is "seventy-seven million, five hundred forty thousand, four hundred thirty-one".