15500421663 has 8 divisors (see below), whose sum is σ = 20702083248. Its totient is φ = 10316187264.

The previous prime is 15500421661. The next prime is 15500421667. The reversal of 15500421663 is 36612400551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 15500421663 - 2¹ = 15500421661 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15500421661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4354720 + ... + 4358277.

It is an arithmetic number, because the mean of its divisors is an integer number (2587760406).

Almost surely, 2^15500421663 is an apocalyptic number.

15500421663 is a deficient number, since it is larger than the sum of its proper divisors (5201661585).

15500421663 is an equidigital number, since it uses as much as digits as its factorization.

15500421663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8713593.

The product of its (nonzero) digits is 21600, while the sum is 33.

The spelling of 15500421663 in words is "fifteen billion, five hundred million, four hundred twenty-one thousand, six hundred sixty-three".