77608421 has 16 divisors (see below), whose sum is σ = 88501248. Its totient is φ = 67426800.

The previous prime is 77608393. The next prime is 77608429. The reversal of 77608421 is 12480677.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77608421 is a prime.

It is a super-2 number, since 2×77608421² = 12046134020226482, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77608429) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20486 + ... + 23976.

It is an arithmetic number, because the mean of its divisors is an integer number (5531328).

Almost surely, 2^77608421 is an apocalyptic number.

It is an amenable number.

77608421 is a deficient number, since it is larger than the sum of its proper divisors (10892827).

77608421 is a wasteful number, since it uses less digits than its factorization.

77608421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3592.

The product of its (nonzero) digits is 18816, while the sum is 35.

The square root of 77608421 is about 8809.5641776424. The cubic root of 77608421 is about 426.5496754301.

The spelling of 77608421 in words is "seventy-seven million, six hundred eight thousand, four hundred twenty-one".