45781721 has 4 divisors (see below), whose sum is σ = 46333392. Its totient is φ = 45230052.

The previous prime is 45781709. The next prime is 45781733. The reversal of 45781721 is 12718754.

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.

It is an interprime number because it is at equal distance from previous prime (45781709) and next prime (45781733).

It is a cyclic number.

It is not a de Polignac number, because 45781721 - 2⁶ = 45781657 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (45781751) 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, 275711 + ... + 275876.

It is an arithmetic number, because the mean of its divisors is an integer number (11583348).

Almost surely, 2^45781721 is an apocalyptic number.

It is an amenable number.

45781721 is a deficient number, since it is larger than the sum of its proper divisors (551671).

45781721 is an equidigital number, since it uses as much as digits as its factorization.

45781721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 551670.

The product of its digits is 15680, while the sum is 35.

The square root of 45781721 is about 6766.2191067094. The cubic root of 45781721 is about 357.7371461909.

The spelling of 45781721 in words is "forty-five million, seven hundred eighty-one thousand, seven hundred twenty-one".