45155721 has 8 divisors (see below), whose sum is σ = 64839040. Its totient is φ = 27788112.

The previous prime is 45155707. The next prime is 45155741. The reversal of 45155721 is 12755154.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 45155721 - 2¹⁸ = 44893577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (45155741) 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, 578881 + ... + 578958.

It is an arithmetic number, because the mean of its divisors is an integer number (8104880).

Almost surely, 2^45155721 is an apocalyptic number.

It is an amenable number.

45155721 is a deficient number, since it is larger than the sum of its proper divisors (19683319).

45155721 is a wasteful number, since it uses less digits than its factorization.

45155721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1157855.

The product of its digits is 7000, while the sum is 30.

The square root of 45155721 is about 6719.8006666865. The cubic root of 45155721 is about 356.0991417896.

The spelling of 45155721 in words is "forty-five million, one hundred fifty-five thousand, seven hundred twenty-one".