45138990 has 32 divisors (see below), whose sum is σ = 116667936. Its totient is φ = 11111040.

The previous prime is 45138979. The next prime is 45139013. The reversal of 45138990 is 9983154.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57481 + ... + 58260.

It is an arithmetic number, because the mean of its divisors is an integer number (3645873).

Almost surely, 2^45138990 is an apocalyptic number.

45138990 is an abundant number, since it is smaller than the sum of its proper divisors (71528946).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

45138990 is a wasteful number, since it uses less digits than its factorization.

45138990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115764.

The product of its (nonzero) digits is 38880, while the sum is 39.

The square root of 45138990 is about 6718.5556483518. Note that the first 3 decimals coincide. The cubic root of 45138990 is about 356.0551559956.

The spelling of 45138990 in words is "forty-five million, one hundred thirty-eight thousand, nine hundred ninety".