21969011 has 4 divisors (see below), whose sum is σ = 22084224. Its totient is φ = 21853800.

The previous prime is 21968983. The next prime is 21969023. The reversal of 21969011 is 11096912.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21969011 - 2¹⁰ = 21967987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21969091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57320 + ... + 57701.

It is an arithmetic number, because the mean of its divisors is an integer number (5521056).

Almost surely, 2^21969011 is an apocalyptic number.

21969011 is a deficient number, since it is larger than the sum of its proper divisors (115213).

21969011 is a wasteful number, since it uses less digits than its factorization.

21969011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115212.

The product of its (nonzero) digits is 972, while the sum is 29.

The square root of 21969011 is about 4687.1111572055. Note that the first 4 decimals coincide. The cubic root of 21969011 is about 280.0723070062.

The spelling of 21969011 in words is "twenty-one million, nine hundred sixty-nine thousand, eleven".