15777297316321 has 4 divisors (see below), whose sum is σ = 16112984493312. Its totient is φ = 15441610139332.

The previous prime is 15777297316279. The next prime is 15777297316367. The reversal of 15777297316321 is 12361379277751.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 15777297316321 - 2⁹ = 15777297315809 is a prime.

It is a super-2 number, since 2×15777297316321² (a number of 27 digits) 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 15777297316321.

It is not an unprimeable number, because it can be changed into a prime (15777297616321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 167843588425 + ... + 167843588518.

It is an arithmetic number, because the mean of its divisors is an integer number (4028246123328).

Almost surely, 2^{15777297316321} is an apocalyptic number.

It is an amenable number.

15777297316321 is a deficient number, since it is larger than the sum of its proper divisors (335687176991).

15777297316321 is an equidigital number, since it uses as much as digits as its factorization.

15777297316321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335687176990.

The product of its digits is 23337720, while the sum is 61.

The spelling of 15777297316321 in words is "fifteen trillion, seven hundred seventy-seven billion, two hundred ninety-seven million, three hundred sixteen thousand, three hundred twenty-one".