45021491 has 4 divisors (see below), whose sum is σ = 47669832. Its totient is φ = 42373152.

The previous prime is 45021467. The next prime is 45021497. The reversal of 45021491 is 19412054.

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 45021491 - 2¹⁰ = 45020467 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 45021491.

It is not an unprimeable number, because it can be changed into a prime (45021497) 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, 1324145 + ... + 1324178.

It is an arithmetic number, because the mean of its divisors is an integer number (11917458).

Almost surely, 2^45021491 is an apocalyptic number.

45021491 is a deficient number, since it is larger than the sum of its proper divisors (2648341).

45021491 is a wasteful number, since it uses less digits than its factorization.

45021491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2648340.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 45021491 is about 6709.8055858572. The cubic root of 45021491 is about 355.7459445441.

The spelling of 45021491 in words is "forty-five million, twenty-one thousand, four hundred ninety-one".