1869961820 has 12 divisors (see below), whose sum is σ = 3926919864. Its totient is φ = 747984720.

The previous prime is 1869961813. The next prime is 1869961859. The reversal of 1869961820 is 281699681.

It is a happy number.

It is a hoax number, since the sum of its digits (50) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 46749026 + ... + 46749065.

It is an arithmetic number, because the mean of its divisors is an integer number (327243322).

Almost surely, 2^1869961820 is an apocalyptic number.

1869961820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1869961820 is an abundant number, since it is smaller than the sum of its proper divisors (2056958044).

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

1869961820 is a wasteful number, since it uses less digits than its factorization.

1869961820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93498100 (or 93498098 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 50.

The square root of 1869961820 is about 43243.0551649626. The cubic root of 1869961820 is about 1232.0005824124. Note that the first 3 decimals are identical.

It can be divided in two parts, 1869961 and 820, that added together give a palindrome (1870781).

The spelling of 1869961820 in words is "one billion, eight hundred sixty-nine million, nine hundred sixty-one thousand, eight hundred twenty".