77121553315 has 4 divisors (see below), whose sum is σ = 92545863984. Its totient is φ = 61697242648.

The previous prime is 77121553309. The next prime is 77121553321. The reversal of 77121553315 is 51335512177.

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

It is an interprime number because it is at equal distance from previous prime (77121553309) and next prime (77121553321).

It is a cyclic number.

It is not a de Polignac number, because 77121553315 - 2¹⁷ = 77121422243 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7712155327 + ... + 7712155336.

It is an arithmetic number, because the mean of its divisors is an integer number (23136465996).

Almost surely, 2^77121553315 is an apocalyptic number.

77121553315 is a deficient number, since it is larger than the sum of its proper divisors (15424310669).

77121553315 is a wasteful number, since it uses less digits than its factorization.

77121553315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15424310668.

The product of its digits is 110250, while the sum is 40.

It can be divided in two parts, 77121 and 553315, that added together give a square (630436 = 794²).

The spelling of 77121553315 in words is "seventy-seven billion, one hundred twenty-one million, five hundred fifty-three thousand, three hundred fifteen".