21966826 has 16 divisors (see below), whose sum is σ = 38676096. Its totient is φ = 9159696.

The previous prime is 21966823. The next prime is 21966827. The reversal of 21966826 is 62866912.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21966823) 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, 20686 + ... + 21721.

It is an arithmetic number, because the mean of its divisors is an integer number (2417256).

Almost surely, 2^21966826 is an apocalyptic number.

21966826 is a deficient number, since it is larger than the sum of its proper divisors (16709270).

21966826 is a wasteful number, since it uses less digits than its factorization.

21966826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42453.

The product of its digits is 62208, while the sum is 40.

The square root of 21966826 is about 4686.8780654077. The cubic root of 21966826 is about 280.0630215285.

The spelling of 21966826 in words is "twenty-one million, nine hundred sixty-six thousand, eight hundred twenty-six".