24720138 has 12 divisors (see below), whose sum is σ = 53560338. Its totient is φ = 8240040.

The previous prime is 24720133. The next prime is 24720149. The reversal of 24720138 is 83102742.

It can be written as a sum of positive squares in only one way, i.e., 17413929 + 7306209 = 4173^2 + 2703^2 .

It is a super-3 number, since 3×24720138³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (24720133) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 686653 + ... + 686688.

Almost surely, 2^24720138 is an apocalyptic number.

24720138 is an abundant number, since it is smaller than the sum of its proper divisors (28840200).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

24720138 is a wasteful number, since it uses less digits than its factorization.

24720138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1373349 (or 1373346 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 24720138 is about 4971.9350357783. The cubic root of 24720138 is about 291.3065816256.

The spelling of 24720138 in words is "twenty-four million, seven hundred twenty thousand, one hundred thirty-eight".