1561155403 has 4 divisors (see below), whose sum is σ = 1561250520. Its totient is φ = 1561060288.

The previous prime is 1561155389. The next prime is 1561155413. The reversal of 1561155403 is 3045511651.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1561155403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1561155413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15925 + ... + 58102.

It is an arithmetic number, because the mean of its divisors is an integer number (390312630).

Almost surely, 2^1561155403 is an apocalyptic number.

1561155403 is a deficient number, since it is larger than the sum of its proper divisors (95117).

1561155403 is an equidigital number, since it uses as much as digits as its factorization.

1561155403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95116.

The product of its (nonzero) digits is 9000, while the sum is 31.

The square root of 1561155403 is about 39511.4591352939. The cubic root of 1561155403 is about 1160.0642560026.

The spelling of 1561155403 in words is "one billion, five hundred sixty-one million, one hundred fifty-five thousand, four hundred three".