21941811 has 12 divisors (see below), whose sum is σ = 31758792. Its totient is φ = 14597856.

The previous prime is 21941807. The next prime is 21941813. The reversal of 21941811 is 11814912.

It is not a de Polignac number, because 21941811 - 2² = 21941807 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21941813) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2695 + ... + 7151.

It is an arithmetic number, because the mean of its divisors is an integer number (2646566).

Almost surely, 2^21941811 is an apocalyptic number.

21941811 is a deficient number, since it is larger than the sum of its proper divisors (9816981).

21941811 is a wasteful number, since it uses less digits than its factorization.

21941811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5010 (or 5007 counting only the distinct ones).

The product of its digits is 576, while the sum is 27.

The square root of 21941811 is about 4684.2086845058. The cubic root of 21941811 is about 279.9566727176.

It can be divided in two parts, 2194 and 1811, that added together give a triangular number (4005 = T₈₉).

The spelling of 21941811 in words is "twenty-one million, nine hundred forty-one thousand, eight hundred eleven".