18821625 has 32 divisors (see below), whose sum is σ = 31943808. Its totient is φ = 9838400.

The previous prime is 18821623. The next prime is 18821633. The reversal of 18821625 is 52612881.

It is not a de Polignac number, because 18821625 - 2¹ = 18821623 is a prime.

It is a super-4 number, since 4×18821625⁴ (a number of 30 digits) contains 4444 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18821623) 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, 19402 + ... + 20348.

It is an arithmetic number, because the mean of its divisors is an integer number (998244).

Almost surely, 2^18821625 is an apocalyptic number.

18821625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18821625 is a deficient number, since it is larger than the sum of its proper divisors (13122183).

18821625 is an equidigital number, since it uses as much as digits as its factorization.

18821625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018 (or 1008 counting only the distinct ones).

The product of its digits is 7680, while the sum is 33.

The square root of 18821625 is about 4338.3896782101. The cubic root of 18821625 is about 266.0024921092.

The spelling of 18821625 in words is "eighteen million, eight hundred twenty-one thousand, six hundred twenty-five".