155498989 has 4 divisors (see below), whose sum is σ = 155525500. Its totient is φ = 155472480.

The previous prime is 155498977. The next prime is 155499031. The reversal of 155498989 is 989894551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 989894551 = 2837 ⋅348923.

It can be written as a sum of positive squares in 2 ways, for example, as 10778089 + 144720900 = 3283^2 + 12030^2 .

It is a cyclic number.

It is not a de Polignac number, because 155498989 - 2⁹ = 155498477 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155498969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 114 + ... + 17635.

It is an arithmetic number, because the mean of its divisors is an integer number (38881375).

Almost surely, 2^155498989 is an apocalyptic number.

It is an amenable number.

155498989 is a deficient number, since it is larger than the sum of its proper divisors (26511).

155498989 is an equidigital number, since it uses as much as digits as its factorization.

155498989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26510.

The product of its digits is 4665600, while the sum is 58.

The square root of 155498989 is about 12469.9233758672. The cubic root of 155498989 is about 537.7443506991.

The spelling of 155498989 in words is "one hundred fifty-five million, four hundred ninety-eight thousand, nine hundred eighty-nine".