1506045721 has 4 divisors (see below), whose sum is σ = 1534461732. Its totient is φ = 1477629712.

The previous prime is 1506045703. The next prime is 1506045733. The reversal of 1506045721 is 1275406051.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 764246025 + 741799696 = 27645^2 + 27236^2 .

It is a cyclic number.

It is not a de Polignac number, because 1506045721 - 2²³ = 1497657113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1506048721) 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, 14207926 + ... + 14208031.

It is an arithmetic number, because the mean of its divisors is an integer number (383615433).

Almost surely, 2^1506045721 is an apocalyptic number.

It is an amenable number.

1506045721 is a deficient number, since it is larger than the sum of its proper divisors (28416011).

1506045721 is an equidigital number, since it uses as much as digits as its factorization.

1506045721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28416010.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 1506045721 is about 38807.8048979841. The cubic root of 1506045721 is about 1146.2500971947.

The spelling of 1506045721 in words is "one billion, five hundred six million, forty-five thousand, seven hundred twenty-one".