45381681 has 8 divisors (see below), whose sum is σ = 67232160. Its totient is φ = 30254436.

The previous prime is 45381673. The next prime is 45381689. The reversal of 45381681 is 18618354.

It is an interprime number because it is at equal distance from previous prime (45381673) and next prime (45381689).

It is not a de Polignac number, because 45381681 - 2³ = 45381673 is a prime.

It is a super-2 number, since 2×45381681² = 4118993940771522, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (45381689) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 840375 + ... + 840428.

It is an arithmetic number, because the mean of its divisors is an integer number (8404020).

Almost surely, 2^45381681 is an apocalyptic number.

It is an amenable number.

45381681 is a deficient number, since it is larger than the sum of its proper divisors (21850479).

45381681 is a wasteful number, since it uses less digits than its factorization.

45381681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1680812 (or 1680806 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 45381681 is about 6736.5926847331. The cubic root of 45381681 is about 356.6921291786.

The spelling of 45381681 in words is "forty-five million, three hundred eighty-one thousand, six hundred eighty-one".