988621591 has 2 divisors, whose sum is σ = 988621592. Its totient is φ = 988621590.

The previous prime is 988621573. The next prime is 988621609. The reversal of 988621591 is 195126889.

It is a balanced prime because it is at equal distance from previous prime (988621573) and next prime (988621609).

It is a cyclic number.

It is not a de Polignac number, because 988621591 - 2⁵ = 988621559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (988621891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494310795 + 494310796.

It is an arithmetic number, because the mean of its divisors is an integer number (494310796).

Almost surely, 2^988621591 is an apocalyptic number.

988621591 is a deficient number, since it is larger than the sum of its proper divisors (1).

988621591 is an equidigital number, since it uses as much as digits as its factorization.

988621591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 49.

The square root of 988621591 is about 31442.3534583530. The cubic root of 988621591 is about 996.1927200151.

The spelling of 988621591 in words is "nine hundred eighty-eight million, six hundred twenty-one thousand, five hundred ninety-one".