1561862417 has 4 divisors (see below), whose sum is σ = 1576191540. Its totient is φ = 1547533296.

The previous prime is 1561862413. The next prime is 1561862431. The reversal of 1561862417 is 7142681651.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 404774161 + 1157088256 = 20119^2 + 34016^2 .

It is a cyclic number.

It is not a de Polignac number, because 1561862417 - 2² = 1561862413 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1561862413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7164398 + ... + 7164615.

It is an arithmetic number, because the mean of its divisors is an integer number (394047885).

Almost surely, 2^1561862417 is an apocalyptic number.

It is an amenable number.

1561862417 is a deficient number, since it is larger than the sum of its proper divisors (14329123).

1561862417 is a wasteful number, since it uses less digits than its factorization.

1561862417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14329122.

The product of its digits is 80640, while the sum is 41.

The square root of 1561862417 is about 39520.4050713046. The cubic root of 1561862417 is about 1160.2393523629.

The spelling of 1561862417 in words is "one billion, five hundred sixty-one million, eight hundred sixty-two thousand, four hundred seventeen".