15464721 has 4 divisors (see below), whose sum is σ = 20619632. Its totient is φ = 10309812.

The previous prime is 15464719. The next prime is 15464731. The reversal of 15464721 is 12746451.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12746451 = 3 ⋅4248817.

It is not a de Polignac number, because 15464721 - 2¹ = 15464719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15464731) 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, 2577451 + ... + 2577456.

It is an arithmetic number, because the mean of its divisors is an integer number (5154908).

Almost surely, 2^15464721 is an apocalyptic number.

It is an amenable number.

15464721 is a deficient number, since it is larger than the sum of its proper divisors (5154911).

15464721 is an equidigital number, since it uses as much as digits as its factorization.

15464721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5154910.

The product of its digits is 6720, while the sum is 30.

The square root of 15464721 is about 3932.5209471788. The cubic root of 15464721 is about 249.1422390169.

The spelling of 15464721 in words is "fifteen million, four hundred sixty-four thousand, seven hundred twenty-one".