21981873151 has 8 divisors (see below), whose sum is σ = 25126585344. Its totient is φ = 18838272120.

The previous prime is 21981873143. The next prime is 21981873157. The reversal of 21981873151 is 15137818912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21981873151 - 2³ = 21981873143 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21981873157) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 234955 + ... + 314908.

It is an arithmetic number, because the mean of its divisors is an integer number (3140823168).

Almost surely, 2^21981873151 is an apocalyptic number.

21981873151 is a deficient number, since it is larger than the sum of its proper divisors (3144712193).

21981873151 is an equidigital number, since it uses as much as digits as its factorization.

21981873151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555581.

The product of its digits is 120960, while the sum is 46.

The spelling of 21981873151 in words is "twenty-one billion, nine hundred eighty-one million, eight hundred seventy-three thousand, one hundred fifty-one".