1371561563 has 4 divisors (see below), whose sum is σ = 1371656448. Its totient is φ = 1371466680.

The previous prime is 1371561557. The next prime is 1371561571. The reversal of 1371561563 is 3651651731.

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-1371561563 is a prime.

It is a super-2 number, since 2×1371561563² = 3762362242198005938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1371561523) 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, 20756 + ... + 56337.

It is an arithmetic number, because the mean of its divisors is an integer number (342914112).

Almost surely, 2^1371561563 is an apocalyptic number.

1371561563 is a deficient number, since it is larger than the sum of its proper divisors (94885).

1371561563 is an equidigital number, since it uses as much as digits as its factorization.

1371561563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94884.

The product of its digits is 56700, while the sum is 38.

The square root of 1371561563 is about 37034.5995388097. The cubic root of 1371561563 is about 1111.0623606118.

The spelling of 1371561563 in words is "one billion, three hundred seventy-one million, five hundred sixty-one thousand, five hundred sixty-three".