77538385 has 4 divisors (see below), whose sum is σ = 93046068. Its totient is φ = 62030704.

The previous prime is 77538379. The next prime is 77538389. The reversal of 77538385 is 58383577.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23853456 + 53684929 = 4884^2 + 7327^2 .

It is a cyclic number.

It is not a de Polignac number, because 77538385 - 2⁵ = 77538353 is a prime.

It is a super-2 number, since 2×77538385² = 12024402296816450, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77538389) 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, 7753834 + ... + 7753843.

It is an arithmetic number, because the mean of its divisors is an integer number (23261517).

Almost surely, 2^77538385 is an apocalyptic number.

It is an amenable number.

77538385 is a deficient number, since it is larger than the sum of its proper divisors (15507683).

77538385 is a wasteful number, since it uses less digits than its factorization.

77538385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15507682.

The product of its digits is 705600, while the sum is 46.

The square root of 77538385 is about 8805.5882824488. The cubic root of 77538385 is about 426.4213267126.

The spelling of 77538385 in words is "seventy-seven million, five hundred thirty-eight thousand, three hundred eighty-five".