1503231561561 has 4 divisors (see below), whose sum is σ = 2004308748752. Its totient is φ = 1002154374372.

The previous prime is 1503231561551. The next prime is 1503231561617. The reversal of 1503231561561 is 1651651323051.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1503231561561 - 2⁵ = 1503231561529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1503231561511) 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, 250538593591 + ... + 250538593596.

It is an arithmetic number, because the mean of its divisors is an integer number (501077187188).

Almost surely, 2^{1503231561561} is an apocalyptic number.

It is an amenable number.

1503231561561 is a deficient number, since it is larger than the sum of its proper divisors (501077187191).

1503231561561 is an equidigital number, since it uses as much as digits as its factorization.

1503231561561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501077187190.

The product of its (nonzero) digits is 81000, while the sum is 39.

The spelling of 1503231561561 in words is "one trillion, five hundred three billion, two hundred thirty-one million, five hundred sixty-one thousand, five hundred sixty-one".