77121957 has 8 divisors (see below), whose sum is σ = 112177440. Its totient is φ = 46740560.

The previous prime is 77121937. The next prime is 77121959. The reversal of 77121957 is 75912177.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77121957 - 2¹⁰ = 77120933 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77121959) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1168482 + ... + 1168547.

It is an arithmetic number, because the mean of its divisors is an integer number (14022180).

Almost surely, 2^77121957 is an apocalyptic number.

It is an amenable number.

77121957 is a deficient number, since it is larger than the sum of its proper divisors (35055483).

77121957 is a wasteful number, since it uses less digits than its factorization.

77121957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2337043.

The product of its digits is 30870, while the sum is 39.

The square root of 77121957 is about 8781.9107829675. The cubic root of 77121957 is about 425.6565759165.

It can be divided in two parts, 7712 and 1957, that added together give a palindrome (9669).

The spelling of 77121957 in words is "seventy-seven million, one hundred twenty-one thousand, nine hundred fifty-seven".