1561371403 has 2 divisors, whose sum is σ = 1561371404. Its totient is φ = 1561371402.

The previous prime is 1561371373. The next prime is 1561371407. The reversal of 1561371403 is 3041731651.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1561371403 is a prime.

It is not a weakly prime, because it can be changed into another prime (1561371407) 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 as a sum of consecutive naturals, namely, 780685701 + 780685702.

It is an arithmetic number, because the mean of its divisors is an integer number (780685702).

Almost surely, 2^1561371403 is an apocalyptic number.

1561371403 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561371403 is an equidigital number, since it uses as much as digits as its factorization.

1561371403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 1561371403 is about 39514.1924250009. The cubic root of 1561371403 is about 1160.1177553368.

The spelling of 1561371403 in words is "one billion, five hundred sixty-one million, three hundred seventy-one thousand, four hundred three".