45217021 has 2 divisors, whose sum is σ = 45217022. Its totient is φ = 45217020.

The previous prime is 45217019. The next prime is 45217031. The reversal of 45217021 is 12071254.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27154521 + 18062500 = 5211^2 + 4250^2 .

It is a cyclic number.

It is not a de Polignac number, because 45217021 - 2¹ = 45217019 is a prime.

It is a super-2 number, since 2×45217021² = 4089157976228882, which contains 22 as substring.

Together with 45217019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 45216983 and 45217001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (45217031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22608510 + 22608511.

It is an arithmetic number, because the mean of its divisors is an integer number (22608511).

Almost surely, 2^45217021 is an apocalyptic number.

It is an amenable number.

45217021 is a deficient number, since it is larger than the sum of its proper divisors (1).

45217021 is an equidigital number, since it uses as much as digits as its factorization.

45217021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 560, while the sum is 22.

The square root of 45217021 is about 6724.3602669696. The cubic root of 45217021 is about 356.2602067046.

Adding to 45217021 its reverse (12071254), we get a palindrome (57288275).

The spelling of 45217021 in words is "forty-five million, two hundred seventeen thousand, twenty-one".