149909813 has 2 divisors, whose sum is σ = 149909814. Its totient is φ = 149909812.

The previous prime is 149909797. The next prime is 149909827. The reversal of 149909813 is 318909941.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 127080529 + 22829284 = 11273^2 + 4778^2 .

It is a cyclic number.

It is not a de Polignac number, because 149909813 - 2⁴ = 149909797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (149909873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74954906 + 74954907.

It is an arithmetic number, because the mean of its divisors is an integer number (74954907).

Almost surely, 2^149909813 is an apocalyptic number.

It is an amenable number.

149909813 is a deficient number, since it is larger than the sum of its proper divisors (1).

149909813 is an equidigital number, since it uses as much as digits as its factorization.

149909813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69984, while the sum is 44.

The square root of 149909813 is about 12243.7662914644. The cubic root of 149909813 is about 531.2227765888. Note that the first 3 decimals are identical.

The spelling of 149909813 in words is "one hundred forty-nine million, nine hundred nine thousand, eight hundred thirteen".