77921231222 has 4 divisors (see below), whose sum is σ = 116881846836. Its totient is φ = 38960615610.

The previous prime is 77921231209. The next prime is 77921231273. The reversal of 77921231222 is 22213212977.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×77921231222² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19480307804 + ... + 19480307807.

It is an arithmetic number, because the mean of its divisors is an integer number (29220461709).

Almost surely, 2^77921231222 is an apocalyptic number.

77921231222 is a deficient number, since it is larger than the sum of its proper divisors (38960615614).

77921231222 is a wasteful number, since it uses less digits than its factorization.

77921231222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38960615613.

The product of its digits is 42336, while the sum is 38.

The spelling of 77921231222 in words is "seventy-seven billion, nine hundred twenty-one million, two hundred thirty-one thousand, two hundred twenty-two".