24690721 has 4 divisors (see below), whose sum is σ = 26935344. Its totient is φ = 22446100.

The previous prime is 24690689. The next prime is 24690727. The reversal of 24690721 is 12709642.

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.

It is a cyclic number.

It is not a de Polignac number, because 24690721 - 2⁵ = 24690689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (24690727) 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, 1122295 + ... + 1122316.

It is an arithmetic number, because the mean of its divisors is an integer number (6733836).

Almost surely, 2^24690721 is an apocalyptic number.

It is an amenable number.

24690721 is a deficient number, since it is larger than the sum of its proper divisors (2244623).

24690721 is a wasteful number, since it uses less digits than its factorization.

24690721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2244622.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 24690721 is about 4968.9758502130. The cubic root of 24690721 is about 291.1909840084.

The spelling of 24690721 in words is "twenty-four million, six hundred ninety thousand, seven hundred twenty-one".