45881981 has 2 divisors, whose sum is σ = 45881982. Its totient is φ = 45881980.

The previous prime is 45881959. The next prime is 45882007. The reversal of 45881981 is 18918854.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36060025 + 9821956 = 6005^2 + 3134^2 .

It is a cyclic number.

It is not a de Polignac number, because 45881981 - 2¹⁸ = 45619837 is a prime.

It is a super-2 number, since 2×45881981² = 4210312360968722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (45881951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22940990 + 22940991.

It is an arithmetic number, because the mean of its divisors is an integer number (22940991).

Almost surely, 2^45881981 is an apocalyptic number.

It is an amenable number.

45881981 is a deficient number, since it is larger than the sum of its proper divisors (1).

45881981 is an equidigital number, since it uses as much as digits as its factorization.

45881981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 92160, while the sum is 44.

The square root of 45881981 is about 6773.6239192917. The cubic root of 45881981 is about 357.9980987800.

The spelling of 45881981 in words is "forty-five million, eight hundred eighty-one thousand, nine hundred eighty-one".