1861899494 has 64 divisors (see below), whose sum is σ = 3562524672. Its totient is φ = 709948800.

The previous prime is 1861899469. The next prime is 1861899497. The reversal of 1861899494 is 4949981681.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861899497) 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 31 ways as a sum of consecutive naturals, for example, 1867004 + ... + 1868000.

It is an arithmetic number, because the mean of its divisors is an integer number (55664448).

Almost surely, 2^1861899494 is an apocalyptic number.

1861899494 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1861899494 is a deficient number, since it is larger than the sum of its proper divisors (1700625178).

1861899494 is a wasteful number, since it uses less digits than its factorization.

1861899494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381.

The product of its digits is 4478976, while the sum is 59.

The square root of 1861899494 is about 43149.7334174847. The cubic root of 1861899494 is about 1230.2274446649.

The spelling of 1861899494 in words is "one billion, eight hundred sixty-one million, eight hundred ninety-nine thousand, four hundred ninety-four".