7249921 has 8 divisors (see below), whose sum is σ = 8317760. Its totient is φ = 6190128.

The previous prime is 7249919. The next prime is 7249927. The reversal of 7249921 is 1299427.

It is a happy number.

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

It is not a de Polignac number, because 7249921 - 2¹ = 7249919 is a prime.

It is a super-2 number, since 2×7249921² = 105122709012482, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

7249921 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (7249927) 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, 70 + ... + 3808.

It is an arithmetic number, because the mean of its divisors is an integer number (1039720).

It is a Proth number, since it is equal to 885 ⋅ 2¹³ + 1 and 885 < 2¹³.

Almost surely, 2^7249921 is an apocalyptic number.

It is an amenable number.

7249921 is a deficient number, since it is larger than the sum of its proper divisors (1067839).

7249921 is a wasteful number, since it uses less digits than its factorization.

7249921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4023.

The product of its digits is 9072, while the sum is 34.

The square root of 7249921 is about 2692.5677335956. The cubic root of 7249921 is about 193.5431290420.

The spelling of 7249921 in words is "seven million, two hundred forty-nine thousand, nine hundred twenty-one".