77613321 has 4 divisors (see below), whose sum is σ = 103484432. Its totient is φ = 51742212.

The previous prime is 77613317. The next prime is 77613331. The reversal of 77613321 is 12331677.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 77613321 - 2² = 77613317 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77613301) 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, 12935551 + ... + 12935556.

It is an arithmetic number, because the mean of its divisors is an integer number (25871108).

Almost surely, 2^77613321 is an apocalyptic number.

It is an amenable number.

77613321 is a deficient number, since it is larger than the sum of its proper divisors (25871111).

77613321 is a wasteful number, since it uses less digits than its factorization.

77613321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25871110.

The product of its digits is 5292, while the sum is 30.

The square root of 77613321 is about 8809.8422800865. The cubic root of 77613321 is about 426.5586523315.

Adding to 77613321 its reverse (12331677), we get a palindrome (89944998).

The spelling of 77613321 in words is "seventy-seven million, six hundred thirteen thousand, three hundred twenty-one".