77199421 has 16 divisors (see below), whose sum is σ = 86531760. Its totient is φ = 68382720.

The previous prime is 77199407. The next prime is 77199443. The reversal of 77199421 is 12499177.

It can be written as a sum of positive squares in 8 ways, for example, as 4284900 + 72914521 = 2070^2 + 8539^2 .

It is a cyclic number.

It is not a de Polignac number, because 77199421 - 2⁵ = 77199389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77199481) 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, 72231 + ... + 73291.

It is an arithmetic number, because the mean of its divisors is an integer number (5408235).

Almost surely, 2^77199421 is an apocalyptic number.

It is an amenable number.

77199421 is a deficient number, since it is larger than the sum of its proper divisors (9332339).

77199421 is a wasteful number, since it uses less digits than its factorization.

77199421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1296.

The product of its digits is 31752, while the sum is 40.

The square root of 77199421 is about 8786.3201057098. The cubic root of 77199421 is about 425.7990430282.

The spelling of 77199421 in words is "seventy-seven million, one hundred ninety-nine thousand, four hundred twenty-one".