8638401249 has 45 divisors (see below), whose sum is σ = 13519838563. Its totient is φ = 5496277248.

The previous prime is 8638401221. The next prime is 8638401253. The reversal of 8638401249 is 9421048368.

It is a happy number.

The square root of 8638401249 is 92943.

It is a perfect power (a square), and thus also a powerful number.

8638401249 is a `hidden beast` number, since 8 + 638 + 4 + 0 + 1 + 2 + 4 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 5279039649 + 3359361600 = 72657^2 + 57960^2 .

It is not a de Polignac number, because 8638401249 - 2⁵ = 8638401217 is a prime.

It is a super-2 number, since 2×8638401249² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8638401649) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 19238977 + ... + 19239425.

Almost surely, 2^8638401249 is an apocalyptic number.

8638401249 is the 92943-rd square number.

8638401249 is the 46472-nd centered octagonal number.

It is an amenable number.

8638401249 is a deficient number, since it is larger than the sum of its proper divisors (4881437314).

8638401249 is an frugal number, since it uses more digits than its factorization.

8638401249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 956 (or 475 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The cubic root of 8638401249 is about 2051.8445621975.

The spelling of 8638401249 in words is "eight billion, six hundred thirty-eight million, four hundred one thousand, two hundred forty-nine".