1821117620 has 48 divisors (see below), whose sum is σ = 4435939200. Its totient is φ = 615060864.

The previous prime is 1821117619. The next prime is 1821117629. The reversal of 1821117620 is 267111281.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1821117629) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 87695 + ... + 106454.

It is an arithmetic number, because the mean of its divisors is an integer number (92415400).

Almost surely, 2^1821117620 is an apocalyptic number.

1821117620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1821117620 is an abundant number, since it is smaller than the sum of its proper divisors (2614821580).

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

1821117620 is a wasteful number, since it uses less digits than its factorization.

1821117620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194232 (or 194230 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 29.

The square root of 1821117620 is about 42674.5547135527. The cubic root of 1821117620 is about 1221.1790134138.

The spelling of 1821117620 in words is "one billion, eight hundred twenty-one million, one hundred seventeen thousand, six hundred twenty".