149981 has 8 divisors (see below), whose sum is σ = 164640. Its totient is φ = 135792.

The previous prime is 149971. The next prime is 149993. The reversal of 149981 is 189941.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 149981 - 2¹⁰ = 148957 is a prime.

It is a super-2 number, since 2×149981² = 44988600722, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (149911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1010 + ... + 1148.

It is an arithmetic number, because the mean of its divisors is an integer number (20580).

2¹⁴⁹⁹⁸¹ is an apocalyptic number.

It is an amenable number.

149981 is a deficient number, since it is larger than the sum of its proper divisors (14659).

149981 is a wasteful number, since it uses less digits than its factorization.

149981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235.

The product of its digits is 2592, while the sum is 32.

The square root of 149981 is about 387.2738049494. The cubic root of 149981 is about 53.1306849741.

The spelling of 149981 in words is "one hundred forty-nine thousand, nine hundred eighty-one".