1861163605 has 16 divisors (see below), whose sum is σ = 2559135744. Its totient is φ = 1272885120.

The previous prime is 1861163593. The next prime is 1861163609. The reversal of 1861163605 is 5063611681.

It is not a de Polignac number, because 1861163605 - 2⁵ = 1861163573 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861163609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56016 + ... + 82825.

It is an arithmetic number, because the mean of its divisors is an integer number (159945984).

Almost surely, 2^1861163605 is an apocalyptic number.

It is an amenable number.

1861163605 is a deficient number, since it is larger than the sum of its proper divisors (697972139).

1861163605 is a wasteful number, since it uses less digits than its factorization.

1861163605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139236.

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 1861163605 is about 43141.2054189495. The cubic root of 1861163605 is about 1230.0653467386.

The spelling of 1861163605 in words is "one billion, eight hundred sixty-one million, one hundred sixty-three thousand, six hundred five".