618140639 has 2 divisors, whose sum is σ = 618140640. Its totient is φ = 618140638.

The previous prime is 618140603. The next prime is 618140657. The reversal of 618140639 is 936041816.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-618140639 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (618140239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 309070319 + 309070320.

It is an arithmetic number, because the mean of its divisors is an integer number (309070320).

Almost surely, 2^618140639 is an apocalyptic number.

618140639 is a deficient number, since it is larger than the sum of its proper divisors (1).

618140639 is an equidigital number, since it uses as much as digits as its factorization.

618140639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 618140639 is about 24862.4342935281. The cubic root of 618140639 is about 851.8486358355.

The spelling of 618140639 in words is "six hundred eighteen million, one hundred forty thousand, six hundred thirty-nine".