21699736 has 16 divisors (see below), whose sum is σ = 40924800. Its totient is φ = 10786464.

The previous prime is 21699697. The next prime is 21699739. The reversal of 21699736 is 63799612.

It is a junction number, because it is equal to n+sod(n) for n = 21699692 and 21699701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21699739) 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 3 ways as a sum of consecutive naturals, for example, 6456 + ... + 9223.

It is an arithmetic number, because the mean of its divisors is an integer number (2557800).

Almost surely, 2^21699736 is an apocalyptic number.

It is an amenable number.

21699736 is a deficient number, since it is larger than the sum of its proper divisors (19225064).

21699736 is a wasteful number, since it uses less digits than its factorization.

21699736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15858 (or 15854 counting only the distinct ones).

The product of its digits is 122472, while the sum is 43.

The square root of 21699736 is about 4658.2975430945. The cubic root of 21699736 is about 278.9233140987.

The spelling of 21699736 in words is "twenty-one million, six hundred ninety-nine thousand, seven hundred thirty-six".