1561237105 has 32 divisors (see below), whose sum is σ = 1940889600. Its totient is φ = 1205131200.

The previous prime is 1561237103. The next prime is 1561237133. The reversal of 1561237105 is 5017321651.

It is not a de Polignac number, because 1561237105 - 2¹ = 1561237103 is a prime.

It is a super-2 number, since 2×1561237105² = 4874922596057562050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1561237103) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5019900 + ... + 5020210.

It is an arithmetic number, because the mean of its divisors is an integer number (60652800).

Almost surely, 2^1561237105 is an apocalyptic number.

It is an amenable number.

1561237105 is a deficient number, since it is larger than the sum of its proper divisors (379652495).

1561237105 is a wasteful number, since it uses less digits than its factorization.

1561237105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645.

The product of its (nonzero) digits is 6300, while the sum is 31.

The square root of 1561237105 is about 39512.4930243588. The cubic root of 1561237105 is about 1160.0844927060.

Adding to 1561237105 its reverse (5017321651), we get a palindrome (6578558756).

The spelling of 1561237105 in words is "one billion, five hundred sixty-one million, two hundred thirty-seven thousand, one hundred five".