103431556561 has 4 divisors (see below), whose sum is σ = 103432203072. Its totient is φ = 103430910052.

The previous prime is 103431556493. The next prime is 103431556573. The reversal of 103431556561 is 165655134301.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 165655134301 = 19 ⋅8718691279.

It is a cyclic number.

It is not a de Polignac number, because 103431556561 - 2⁷ = 103431556433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (103431557561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112740 + ... + 468586.

It is an arithmetic number, because the mean of its divisors is an integer number (25858050768).

Almost surely, 2^103431556561 is an apocalyptic number.

It is an amenable number.

103431556561 is a deficient number, since it is larger than the sum of its proper divisors (646511).

103431556561 is an equidigital number, since it uses as much as digits as its factorization.

103431556561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646510.

The product of its (nonzero) digits is 162000, while the sum is 40.

The spelling of 103431556561 in words is "one hundred three billion, four hundred thirty-one million, five hundred fifty-six thousand, five hundred sixty-one".