15539984639 has 2 divisors, whose sum is σ = 15539984640. Its totient is φ = 15539984638.

The previous prime is 15539984591. The next prime is 15539984683. The reversal of 15539984639 is 93648993551.

It is a strong prime.

It is an emirp because it is prime and its reverse (93648993551) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15539984639 is a prime.

It is a super-2 number, since 2×15539984639² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15539989639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7769992319 + 7769992320.

It is an arithmetic number, because the mean of its divisors is an integer number (7769992320).

Almost surely, 2^15539984639 is an apocalyptic number.

15539984639 is a deficient number, since it is larger than the sum of its proper divisors (1).

15539984639 is an equidigital number, since it uses as much as digits as its factorization.

15539984639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31492800, while the sum is 62.

The spelling of 15539984639 in words is "fifteen billion, five hundred thirty-nine million, nine hundred eighty-four thousand, six hundred thirty-nine".