45138981 has 4 divisors (see below), whose sum is σ = 60185312. Its totient is φ = 30092652.

The previous prime is 45138979. The next prime is 45139013. The reversal of 45138981 is 18983154.

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 not a de Polignac number, because 45138981 - 2¹ = 45138979 is a prime.

It is a super-2 number, since 2×45138981² = 4075055211436722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (45138901) 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, 7523161 + ... + 7523166.

It is an arithmetic number, because the mean of its divisors is an integer number (15046328).

Almost surely, 2^45138981 is an apocalyptic number.

It is an amenable number.

45138981 is a deficient number, since it is larger than the sum of its proper divisors (15046331).

45138981 is a wasteful number, since it uses less digits than its factorization.

45138981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15046330.

The product of its digits is 34560, while the sum is 39.

The square root of 45138981 is about 6718.5549785650. The cubic root of 45138981 is about 356.0551323317.

The spelling of 45138981 in words is "forty-five million, one hundred thirty-eight thousand, nine hundred eighty-one".