21969069 has 8 divisors (see below), whose sum is σ = 29915520. Its totient is φ = 14334336.

The previous prime is 21969029. The next prime is 21969091. The reversal of 21969069 is 96096912.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21969069 - 2⁷ = 21968941 is a prime.

It is a super-2 number, since 2×21969069² = 965279985453522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 21969069.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21969029) 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, 77764 + ... + 78045.

It is an arithmetic number, because the mean of its divisors is an integer number (3739440).

Almost surely, 2^21969069 is an apocalyptic number.

It is an amenable number.

21969069 is a deficient number, since it is larger than the sum of its proper divisors (7946451).

21969069 is a wasteful number, since it uses less digits than its factorization.

21969069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155859.

The product of its (nonzero) digits is 52488, while the sum is 42.

The square root of 21969069 is about 4687.1173443813. The cubic root of 21969069 is about 280.0725534773.

The spelling of 21969069 in words is "twenty-one million, nine hundred sixty-nine thousand, sixty-nine".