1561170020 has 12 divisors (see below), whose sum is σ = 3278457084. Its totient is φ = 624468000.

The previous prime is 1561170019. The next prime is 1561170097. The reversal of 1561170020 is 200711651.

It can be written as a sum of positive squares in 2 ways, for example, as 1042514944 + 518655076 = 32288^2 + 22774^2 .

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 39029231 + ... + 39029270.

It is an arithmetic number, because the mean of its divisors is an integer number (273204757).

Almost surely, 2^1561170020 is an apocalyptic number.

1561170020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1561170020 is an abundant number, since it is smaller than the sum of its proper divisors (1717287064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1561170020 is a wasteful number, since it uses less digits than its factorization.

1561170020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78058510 (or 78058508 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 1561170020 is about 39511.6441065162. The cubic root of 1561170020 is about 1160.0678765276.

Adding to 1561170020 its reverse (200711651), we get a palindrome (1761881671).

The spelling of 1561170020 in words is "one billion, five hundred sixty-one million, one hundred seventy thousand, twenty".