1620684081 has 12 divisors (see below), whose sum is σ = 2361706308. Its totient is φ = 1070893824.

The previous prime is 1620684041. The next prime is 1620684083. The reversal of 1620684081 is 1804860261.

It can be written as a sum of positive squares in 2 ways, for example, as 11390625 + 1609293456 = 3375^2 + 40116^2 .

It is not a de Polignac number, because 1620684081 - 2²⁶ = 1553575217 is a prime.

It is a super-2 number, since 2×1620684081² = 5253233780813629122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1620684083) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 795780 + ... + 797813.

It is an arithmetic number, because the mean of its divisors is an integer number (196808859).

Almost surely, 2^1620684081 is an apocalyptic number.

It is an amenable number.

1620684081 is a deficient number, since it is larger than the sum of its proper divisors (741022227).

1620684081 is a wasteful number, since it uses less digits than its factorization.

1620684081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1593712 (or 1593709 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 1620684081 is about 40257.7207626065. The cubic root of 1620684081 is about 1174.6255830728.

The spelling of 1620684081 in words is "one billion, six hundred twenty million, six hundred eighty-four thousand, eighty-one".