988830691921 has 2 divisors, whose sum is σ = 988830691922. Its totient is φ = 988830691920.

The previous prime is 988830691909. The next prime is 988830692033. The reversal of 988830691921 is 129196038889.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 777818163600 + 211012528321 = 881940^2 + 459361^2 .

It is a cyclic number.

It is not a de Polignac number, because 988830691921 - 2¹⁷ = 988830560849 is a prime.

It is a super-2 number, since 2×988830691921² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (988830691621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494415345960 + 494415345961.

It is an arithmetic number, because the mean of its divisors is an integer number (494415345961).

Almost surely, 2^988830691921 is an apocalyptic number.

It is an amenable number.

988830691921 is a deficient number, since it is larger than the sum of its proper divisors (1).

988830691921 is an equidigital number, since it uses as much as digits as its factorization.

988830691921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13436928, while the sum is 64.

The spelling of 988830691921 in words is "nine hundred eighty-eight billion, eight hundred thirty million, six hundred ninety-one thousand, nine hundred twenty-one".