1821980433 has 32 divisors (see below), whose sum is σ = 3147289600. Its totient is φ = 910460736.

The previous prime is 1821980429. The next prime is 1821980437. The reversal of 1821980433 is 3340891281.

It is an interprime number because it is at equal distance from previous prime (1821980429) and next prime (1821980437).

It is not a de Polignac number, because 1821980433 - 2² = 1821980429 is a prime.

It is a super-2 number, since 2×1821980433² = 6639225396469734978, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a junction number, because it is equal to n+sod(n) for n = 1821980391 and 1821980400.

It is not an unprimeable number, because it can be changed into a prime (1821980437) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 170443 + ... + 180816.

It is an arithmetic number, because the mean of its divisors is an integer number (98352800).

Almost surely, 2^1821980433 is an apocalyptic number.

1821980433 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1821980433 is a deficient number, since it is larger than the sum of its proper divisors (1325309167).

1821980433 is a wasteful number, since it uses less digits than its factorization.

1821980433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351301.

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 1821980433 is about 42684.6627373346. The cubic root of 1821980433 is about 1221.3718405657.

The spelling of 1821980433 in words is "one billion, eight hundred twenty-one million, nine hundred eighty thousand, four hundred thirty-three".