21693801 has 32 divisors (see below), whose sum is σ = 31933440. Its totient is φ = 13051584.

The previous prime is 21693799. The next prime is 21693811. The reversal of 21693801 is 10839612.

It is not a de Polignac number, because 21693801 - 2¹ = 21693799 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21693811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 129820 + ... + 129986.

It is an arithmetic number, because the mean of its divisors is an integer number (997920).

Almost surely, 2^21693801 is an apocalyptic number.

It is an amenable number.

21693801 is a deficient number, since it is larger than the sum of its proper divisors (10239639).

21693801 is a wasteful number, since it uses less digits than its factorization.

21693801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 21693801 is about 4657.6604642245. The cubic root of 21693801 is about 278.8978827477.

The spelling of 21693801 in words is "twenty-one million, six hundred ninety-three thousand, eight hundred one".