9149721 has 24 divisors (see below), whose sum is σ = 14418720. Its totient is φ = 5144832.

The previous prime is 9149717. The next prime is 9149729. The reversal of 9149721 is 1279419.

9149721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9149721 - 2² = 9149717 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9149729) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9385 + ... + 10313.

It is an arithmetic number, because the mean of its divisors is an integer number (600780).

Almost surely, 2^9149721 is an apocalyptic number.

It is an amenable number.

9149721 is a deficient number, since it is larger than the sum of its proper divisors (5268999).

9149721 is a wasteful number, since it uses less digits than its factorization.

9149721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1013 (or 1006 counting only the distinct ones).

The product of its digits is 4536, while the sum is 33.

The square root of 9149721 is about 3024.8505748218. The cubic root of 9149721 is about 209.1554973234.

It can be divided in two parts, 9149 and 721, that added together give a triangular number (9870 = T₁₄₀).

The spelling of 9149721 in words is "nine million, one hundred forty-nine thousand, seven hundred twenty-one".