149551691 has 2 divisors, whose sum is σ = 149551692. Its totient is φ = 149551690.

The previous prime is 149551643. The next prime is 149551709. The reversal of 149551691 is 196155941.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-149551691 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (149551991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74775845 + 74775846.

It is an arithmetic number, because the mean of its divisors is an integer number (74775846).

Almost surely, 2^149551691 is an apocalyptic number.

149551691 is a deficient number, since it is larger than the sum of its proper divisors (1).

149551691 is an equidigital number, since it uses as much as digits as its factorization.

149551691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48600, while the sum is 41.

The square root of 149551691 is about 12229.1328801350. The cubic root of 149551691 is about 530.7994237032.

The spelling of 149551691 in words is "one hundred forty-nine million, five hundred fifty-one thousand, six hundred ninety-one".