989687978431 has 2 divisors, whose sum is σ = 989687978432. Its totient is φ = 989687978430.

The previous prime is 989687978359. The next prime is 989687978437. The reversal of 989687978431 is 134879786989.

989687978431 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 989687978431 - 2¹³ = 989687970239 is a prime.

It is a super-2 number, since 2×989687978431² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (989687978437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494843989215 + 494843989216.

It is an arithmetic number, because the mean of its divisors is an integer number (494843989216).

Almost surely, 2^989687978431 is an apocalyptic number.

989687978431 is a deficient number, since it is larger than the sum of its proper divisors (1).

989687978431 is an equidigital number, since it uses as much as digits as its factorization.

989687978431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1316818944, while the sum is 79.

The spelling of 989687978431 in words is "nine hundred eighty-nine billion, six hundred eighty-seven million, nine hundred seventy-eight thousand, four hundred thirty-one".