6621237881 has 2 divisors, whose sum is σ = 6621237882. Its totient is φ = 6621237880.

The previous prime is 6621237871. The next prime is 6621237893. The reversal of 6621237881 is 1887321266.

6621237881 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5508014656 + 1113223225 = 74216^2 + 33365^2 .

It is a cyclic number.

It is not a de Polignac number, because 6621237881 - 2⁶ = 6621237817 is a prime.

It is a super-2 number, since 2×6621237881² = 87681582153578740322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6621237871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3310618940 + 3310618941.

It is an arithmetic number, because the mean of its divisors is an integer number (3310618941).

Almost surely, 2^6621237881 is an apocalyptic number.

It is an amenable number.

6621237881 is a deficient number, since it is larger than the sum of its proper divisors (1).

6621237881 is an equidigital number, since it uses as much as digits as its factorization.

6621237881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 193536, while the sum is 44.

The square root of 6621237881 is about 81370.9891853356. The cubic root of 6621237881 is about 1877.7872979959.

The spelling of 6621237881 in words is "six billion, six hundred twenty-one million, two hundred thirty-seven thousand, eight hundred eighty-one".