24721989 has 4 divisors (see below), whose sum is σ = 32962656. Its totient is φ = 16481324.

The previous prime is 24721981. The next prime is 24721993. The reversal of 24721989 is 98912742.

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 24721989 - 2³ = 24721981 is a prime.

It is a super-2 number, since 2×24721989² = 1222353480232242, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 24721989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (24721981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4120329 + ... + 4120334.

It is an arithmetic number, because the mean of its divisors is an integer number (8240664).

Almost surely, 2^24721989 is an apocalyptic number.

It is an amenable number.

24721989 is a deficient number, since it is larger than the sum of its proper divisors (8240667).

24721989 is an equidigital number, since it uses as much as digits as its factorization.

24721989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8240666.

The product of its digits is 72576, while the sum is 42.

The square root of 24721989 is about 4972.1211771235. The cubic root of 24721989 is about 291.3138522838.

The spelling of 24721989 in words is "twenty-four million, seven hundred twenty-one thousand, nine hundred eighty-nine".