145997131 has 4 divisors (see below), whose sum is σ = 166853872. Its totient is φ = 125140392.

The previous prime is 145997129. The next prime is 145997141. The reversal of 145997131 is 131799541.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 145997131 - 2¹ = 145997129 is a prime.

It is a super-2 number, since 2×145997131² = 42630324520462322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145997141) 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, 10428360 + ... + 10428373.

It is an arithmetic number, because the mean of its divisors is an integer number (41713468).

Almost surely, 2^145997131 is an apocalyptic number.

145997131 is a deficient number, since it is larger than the sum of its proper divisors (20856741).

145997131 is an equidigital number, since it uses as much as digits as its factorization.

145997131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20856740.

The product of its digits is 34020, while the sum is 40.

The square root of 145997131 is about 12082.9272529466. The cubic root of 145997131 is about 526.5602936818.

The spelling of 145997131 in words is "one hundred forty-five million, nine hundred ninety-seven thousand, one hundred thirty-one".