149897581 has 2 divisors, whose sum is σ = 149897582. Its totient is φ = 149897580.

The previous prime is 149897537. The next prime is 149897603. The reversal of 149897581 is 185798941.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 129276900 + 20620681 = 11370^2 + 4541^2 .

It is a cyclic number.

It is not a de Polignac number, because 149897581 - 2²³ = 141508973 is a prime.

It is a super-2 number, since 2×149897581² = 44938569579303122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (149892581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74948790 + 74948791.

It is an arithmetic number, because the mean of its divisors is an integer number (74948791).

Almost surely, 2^149897581 is an apocalyptic number.

It is an amenable number.

149897581 is a deficient number, since it is larger than the sum of its proper divisors (1).

149897581 is an equidigital number, since it uses as much as digits as its factorization.

149897581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 725760, while the sum is 52.

The square root of 149897581 is about 12243.2667617756. The cubic root of 149897581 is about 531.2083276932.

The spelling of 149897581 in words is "one hundred forty-nine million, eight hundred ninety-seven thousand, five hundred eighty-one".