149720521 has 4 divisors (see below), whose sum is σ = 152906112. Its totient is φ = 146534932.

The previous prime is 149720503. The next prime is 149720531. The reversal of 149720521 is 125027941.

149720521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, and also an emirpimes, since its reverse is a distinct semiprime: 125027941 = 1913 ⋅65357.

It is a cyclic number.

It is not a de Polignac number, because 149720521 - 2⁵ = 149720489 is a prime.

It is a super-2 number, since 2×149720521² = 44832468817022882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (149720531) 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, 1592725 + ... + 1592818.

It is an arithmetic number, because the mean of its divisors is an integer number (38226528).

Almost surely, 2^149720521 is an apocalyptic number.

It is an amenable number.

149720521 is a deficient number, since it is larger than the sum of its proper divisors (3185591).

149720521 is an equidigital number, since it uses as much as digits as its factorization.

149720521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3185590.

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 149720521 is about 12236.0337119509. The cubic root of 149720521 is about 530.9990897071. Note that the first 3 decimals are identical.

The spelling of 149720521 in words is "one hundred forty-nine million, seven hundred twenty thousand, five hundred twenty-one".