77121407 has 24 divisors (see below), whose sum is σ = 88252416. Its totient is φ = 67298000.

The previous prime is 77121391. The next prime is 77121419. The reversal of 77121407 is 70412177.

It is not a de Polignac number, because 77121407 - 2⁴ = 77121391 is a prime.

It is a super-2 number, since 2×77121407² = 11895422835319298, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 77121407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77121467) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 403682 + ... + 403872.

It is an arithmetic number, because the mean of its divisors is an integer number (3677184).

Almost surely, 2^77121407 is an apocalyptic number.

77121407 is a deficient number, since it is larger than the sum of its proper divisors (11131009).

77121407 is a wasteful number, since it uses less digits than its factorization.

77121407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331 (or 320 counting only the distinct ones).

The product of its (nonzero) digits is 2744, while the sum is 29.

The square root of 77121407 is about 8781.8794685420. The cubic root of 77121407 is about 425.6555640487.

It can be divided in two parts, 7712 and 1407, that added together give a palindrome (9119).

The spelling of 77121407 in words is "seventy-seven million, one hundred twenty-one thousand, four hundred seven".