77638749 has 8 divisors (see below), whose sum is σ = 105273120. Its totient is φ = 50881776.

The previous prime is 77638739. The next prime is 77638763. The reversal of 77638749 is 94783677.

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

It is not a de Polignac number, because 77638749 - 2⁷ = 77638621 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77638709) 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, 219142 + ... + 219495.

It is an arithmetic number, because the mean of its divisors is an integer number (13159140).

Almost surely, 2^77638749 is an apocalyptic number.

It is an amenable number.

77638749 is a deficient number, since it is larger than the sum of its proper divisors (27634371).

77638749 is a wasteful number, since it uses less digits than its factorization.

77638749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438699.

The product of its digits is 1778112, while the sum is 51.

The square root of 77638749 is about 8811.2853205421. The cubic root of 77638749 is about 426.6052308868.

It can be divided in two parts, 77638 and 749, that added together give a palindrome (78387).

The spelling of 77638749 in words is "seventy-seven million, six hundred thirty-eight thousand, seven hundred forty-nine".