77142215 has 12 divisors (see below), whose sum is σ = 94881864. Its totient is φ = 60177936.

The previous prime is 77142211. The next prime is 77142251. The reversal of 77142215 is 51224177.

It is not a de Polignac number, because 77142215 - 2² = 77142211 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 (77142211) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 128486 + ... + 129084.

It is an arithmetic number, because the mean of its divisors is an integer number (7906822).

Almost surely, 2^77142215 is an apocalyptic number.

77142215 is a deficient number, since it is larger than the sum of its proper divisors (17739649).

77142215 is an frugal number, since it uses more digits than its factorization.

77142215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1246 (or 647 counting only the distinct ones).

The product of its digits is 3920, while the sum is 29.

The square root of 77142215 is about 8783.0641008705. The cubic root of 77142215 is about 425.6938424155.

The spelling of 77142215 in words is "seventy-seven million, one hundred forty-two thousand, two hundred fifteen".