21847865188900 has 27 divisors (see below), whose sum is σ = 47409968889619. Its totient is φ = 8739127378880.

The previous prime is 21847865188871. The next prime is 21847865188907. The reversal of 21847865188900 is 988156874812.

It is a happy number.

The square root of 21847865188900 is 4674170.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 5415608505316 + 16432256683584 = 2327146^2 + 4053672^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21847865188907) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 46507992 + ... + 46975408.

Almost surely, 2^{21847865188900} is an apocalyptic number.

21847865188900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

21847865188900 is the 4674170-th square number.

It is an amenable number.

21847865188900 is an abundant number, since it is smaller than the sum of its proper divisors (25562103700719).

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

21847865188900 is an frugal number, since it uses more digits than its factorization.

21847865188900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 934848 (or 467424 counting only the distinct ones).

The product of its (nonzero) digits is 61931520, while the sum is 67.

The spelling of 21847865188900 in words is "twenty-one trillion, eight hundred forty-seven billion, eight hundred sixty-five million, one hundred eighty-eight thousand, nine hundred".