1561986051 has 16 divisors (see below), whose sum is σ = 2223741696. Its totient is φ = 972883296.

The previous prime is 1561985983. The next prime is 1561986059. The reversal of 1561986051 is 1506891651.

It is not a de Polignac number, because 1561986051 - 2¹⁰ = 1561985027 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1561985994 and 1561986012.

It is not an unprimeable number, because it can be changed into a prime (1561986059) 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 15 ways as a sum of consecutive naturals, for example, 260260 + ... + 266193.

It is an arithmetic number, because the mean of its divisors is an integer number (138983856).

Almost surely, 2^1561986051 is an apocalyptic number.

1561986051 is a deficient number, since it is larger than the sum of its proper divisors (661755645).

1561986051 is a wasteful number, since it uses less digits than its factorization.

1561986051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 526522.

The product of its (nonzero) digits is 64800, while the sum is 42.

The square root of 1561986051 is about 39521.9692196631. The cubic root of 1561986051 is about 1160.2699656542.

The spelling of 1561986051 in words is "one billion, five hundred sixty-one million, nine hundred eighty-six thousand, fifty-one".