77399681 has 8 divisors (see below), whose sum is σ = 79176960. Its totient is φ = 75638032.

The previous prime is 77399603. The next prime is 77399683. The reversal of 77399681 is 18699377.

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 77399681 - 2¹⁴ = 77383297 is a prime.

It is a super-2 number, since 2×77399681² = 11981421237803522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (77399683) 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, 6416 + ... + 13998.

It is an arithmetic number, because the mean of its divisors is an integer number (9897120).

Almost surely, 2^77399681 is an apocalyptic number.

It is an amenable number.

77399681 is a deficient number, since it is larger than the sum of its proper divisors (1777279).

77399681 is a wasteful number, since it uses less digits than its factorization.

77399681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7815.

The product of its digits is 571536, while the sum is 50.

The square root of 77399681 is about 8797.7088494676. The cubic root of 77399681 is about 426.1669080071.

The spelling of 77399681 in words is "seventy-seven million, three hundred ninety-nine thousand, six hundred eighty-one".