77423557 has 8 divisors (see below), whose sum is σ = 78416856. Its totient is φ = 76434432.

The previous prime is 77423551. The next prime is 77423587. The reversal of 77423557 is 75532477.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6964321 + 70459236 = 2639^2 + 8394^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77423557 - 2²³ = 69034949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77423551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53313 + ... + 54745.

It is an arithmetic number, because the mean of its divisors is an integer number (9802107).

Almost surely, 2^77423557 is an apocalyptic number.

It is an amenable number.

77423557 is a deficient number, since it is larger than the sum of its proper divisors (993299).

77423557 is a wasteful number, since it uses less digits than its factorization.

77423557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2087.

The product of its digits is 205800, while the sum is 40.

The square root of 77423557 is about 8799.0656890377. The cubic root of 77423557 is about 426.2107243591.

The spelling of 77423557 in words is "seventy-seven million, four hundred twenty-three thousand, five hundred fifty-seven".