1561151205 has 16 divisors (see below), whose sum is σ = 2775380160. Its totient is φ = 832613904.

The previous prime is 1561151177. The next prime is 1561151213. The reversal of 1561151205 is 5021511651.

It is not a de Polignac number, because 1561151205 - 2¹⁵ = 1561118437 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5781907 + ... + 5782176.

It is an arithmetic number, because the mean of its divisors is an integer number (173461260).

Almost surely, 2^1561151205 is an apocalyptic number.

1561151205 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1561151205 is a deficient number, since it is larger than the sum of its proper divisors (1214228955).

1561151205 is a wasteful number, since it uses less digits than its factorization.

1561151205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11564097 (or 11564091 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 27.

The square root of 1561151205 is about 39511.4060114292. The cubic root of 1561151205 is about 1160.0632161843.

Adding to 1561151205 its reverse (5021511651), we get a palindrome (6582662856).

The spelling of 1561151205 in words is "one billion, five hundred sixty-one million, one hundred fifty-one thousand, two hundred five".