45991021 has 2 divisors, whose sum is σ = 45991022. Its totient is φ = 45991020.

The previous prime is 45991019. The next prime is 45991063. The reversal of 45991021 is 12019954.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40182921 + 5808100 = 6339^2 + 2410^2 .

It is a cyclic number.

It is not a de Polignac number, because 45991021 - 2¹ = 45991019 is a prime.

Together with 45991019, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (45991921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22995510 + 22995511.

It is an arithmetic number, because the mean of its divisors is an integer number (22995511).

Almost surely, 2^45991021 is an apocalyptic number.

It is an amenable number.

45991021 is a deficient number, since it is larger than the sum of its proper divisors (1).

45991021 is an equidigital number, since it uses as much as digits as its factorization.

45991021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 31.

The square root of 45991021 is about 6781.6680101580. The cubic root of 45991021 is about 358.2814724057.

The spelling of 45991021 in words is "forty-five million, nine hundred ninety-one thousand, twenty-one".