15320537661 has 24 divisors (see below), whose sum is σ = 24130473696. Its totient is φ = 8570927040.

The previous prime is 15320537623. The next prime is 15320537707. The reversal of 15320537661 is 16673502351.

It is not a de Polignac number, because 15320537661 - 2⁹ = 15320537149 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15320533661) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1367970 + ... + 1379123.

It is an arithmetic number, because the mean of its divisors is an integer number (1005436404).

Almost surely, 2^15320537661 is an apocalyptic number.

15320537661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

15320537661 is a deficient number, since it is larger than the sum of its proper divisors (8809936035).

15320537661 is a wasteful number, since it uses less digits than its factorization.

15320537661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2747133 (or 2747120 counting only the distinct ones).

The product of its (nonzero) digits is 113400, while the sum is 39.

The spelling of 15320537661 in words is "fifteen billion, three hundred twenty million, five hundred thirty-seven thousand, six hundred sixty-one".