15949766389 has 4 divisors (see below), whose sum is σ = 16018220556. Its totient is φ = 15881312224.

The previous prime is 15949766377. The next prime is 15949766407. The reversal of 15949766389 is 98366794951.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98366794951 = 211 ⋅466193341.

It can be written as a sum of positive squares in 2 ways, for example, as 6055485489 + 9894280900 = 77817^2 + 99470^2 .

It is a cyclic number.

It is not a de Polignac number, because 15949766389 - 2⁹ = 15949765877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15949766089) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34226734 + ... + 34227199.

It is an arithmetic number, because the mean of its divisors is an integer number (4004555139).

Almost surely, 2^15949766389 is an apocalyptic number.

It is an amenable number.

15949766389 is a deficient number, since it is larger than the sum of its proper divisors (68454167).

15949766389 is an equidigital number, since it uses as much as digits as its factorization.

15949766389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68454166.

The product of its digits is 88179840, while the sum is 67.

The spelling of 15949766389 in words is "fifteen billion, nine hundred forty-nine million, seven hundred sixty-six thousand, three hundred eighty-nine".