45215021 has 4 divisors (see below), whose sum is σ = 45234432. Its totient is φ = 45195612.

The previous prime is 45214993. The next prime is 45215099. The reversal of 45215021 is 12051254.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12051254 = 2 ⋅6025627.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-45215021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 45214984 and 45215002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (45215921) 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, 5645 + ... + 11058.

It is an arithmetic number, because the mean of its divisors is an integer number (11308608).

Almost surely, 2^45215021 is an apocalyptic number.

It is an amenable number.

45215021 is a deficient number, since it is larger than the sum of its proper divisors (19411).

45215021 is a wasteful number, since it uses less digits than its factorization.

45215021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19410.

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 45215021 is about 6724.2115522937. The cubic root of 45215021 is about 356.2549540298.

Adding to 45215021 its reverse (12051254), we get a palindrome (57266275).

The spelling of 45215021 in words is "forty-five million, two hundred fifteen thousand, twenty-one".