22721497 has 4 divisors (see below), whose sum is σ = 22731136. Its totient is φ = 22711860.

The previous prime is 22721483. The next prime is 22721507. The reversal of 22721497 is 79412722.

It is a happy number.

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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 79412722 = 2 ⋅39706361.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22721497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22721417) 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, 1348 + ... + 6874.

It is an arithmetic number, because the mean of its divisors is an integer number (5682784).

Almost surely, 2^22721497 is an apocalyptic number.

It is an amenable number.

22721497 is a deficient number, since it is larger than the sum of its proper divisors (9639).

22721497 is an equidigital number, since it uses as much as digits as its factorization.

22721497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9638.

The product of its digits is 14112, while the sum is 34.

The square root of 22721497 is about 4766.7071443503. The cubic root of 22721497 is about 283.2341704502.

The spelling of 22721497 in words is "twenty-two million, seven hundred twenty-one thousand, four hundred ninety-seven".