20185551721888 has 48 divisors (see below), whose sum is σ = 45964690107840. Its totient is φ = 8546722407936.

The previous prime is 20185551721831. The next prime is 20185551721921. The reversal of 20185551721888 is 88812715558102.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 542837253 + ... + 542874436.

It is an arithmetic number, because the mean of its divisors is an integer number (957597710580).

Almost surely, 2^{20185551721888} is an apocalyptic number.

20185551721888 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

20185551721888 is an abundant number, since it is smaller than the sum of its proper divisors (25779138385952).

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

20185551721888 is a wasteful number, since it uses less digits than its factorization.

20185551721888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1085711789 (or 1085711781 counting only the distinct ones).

The product of its (nonzero) digits is 14336000, while the sum is 61.

The spelling of 20185551721888 in words is "twenty trillion, one hundred eighty-five billion, five hundred fifty-one million, seven hundred twenty-one thousand, eight hundred eighty-eight".