999999997764121 has 16 divisors (see below), whose sum is σ = 1012973500464640. Its totient is φ = 987034396158720.

The previous prime is 999999997764101. The next prime is 999999997764161. The reversal of 999999997764121 is 121467799999999.

It is a cyclic number.

It is not a de Polignac number, because 999999997764121 - 2⁷ = 999999997763993 is a prime.

It is a pancake number, because a pancake can be divided into 999999997764121 parts by 44721359 straight cuts.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 999999997763999 and 999999997764017.

It is not an unprimeable number, because it can be changed into a prime (999999997764101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14696986861 + ... + 14697054901.

It is an arithmetic number, because the mean of its divisors is an integer number (63310843779040).

Almost surely, 2^{999999997764121} is an apocalyptic number.

It is an amenable number.

999999997764121 is a deficient number, since it is larger than the sum of its proper divisors (12973502700519).

999999997764121 is a wasteful number, since it uses less digits than its factorization.

999999997764121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123304.

The product of its digits is 101245887792, while the sum is 100.

The spelling of 999999997764121 in words is "nine hundred ninety-nine trillion, nine hundred ninety-nine billion, nine hundred ninety-seven million, seven hundred sixty-four thousand, one hundred twenty-one".