149681661 has 4 divisors (see below), whose sum is σ = 199575552. Its totient is φ = 99787772.

The previous prime is 149681657. The next prime is 149681681. The reversal of 149681661 is 166186941.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 149681661 - 2² = 149681657 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (149681621) 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, 24946941 + ... + 24946946.

It is an arithmetic number, because the mean of its divisors is an integer number (49893888).

Almost surely, 2^149681661 is an apocalyptic number.

It is an amenable number.

149681661 is a deficient number, since it is larger than the sum of its proper divisors (49893891).

149681661 is an equidigital number, since it uses as much as digits as its factorization.

149681661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49893890.

The product of its digits is 62208, while the sum is 42.

The square root of 149681661 is about 12234.4456760411. The cubic root of 149681661 is about 530.9531454148.

The spelling of 149681661 in words is "one hundred forty-nine million, six hundred eighty-one thousand, six hundred sixty-one".