989915893 has 2 divisors, whose sum is σ = 989915894. Its totient is φ = 989915892.

The previous prime is 989915887. The next prime is 989915897. The reversal of 989915893 is 398519989.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 787195249 + 202720644 = 28057^2 + 14238^2 .

It is a cyclic number.

It is not a de Polignac number, because 989915893 - 2²⁹ = 453044981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (989915897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494957946 + 494957947.

It is an arithmetic number, because the mean of its divisors is an integer number (494957947).

Almost surely, 2^989915893 is an apocalyptic number.

It is an amenable number.

989915893 is a deficient number, since it is larger than the sum of its proper divisors (1).

989915893 is an equidigital number, since it uses as much as digits as its factorization.

989915893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6298560, while the sum is 61.

The square root of 989915893 is about 31462.9288687496. The cubic root of 989915893 is about 996.6272684707.

The spelling of 989915893 in words is "nine hundred eighty-nine million, nine hundred fifteen thousand, eight hundred ninety-three".