20969523 has 40 divisors (see below), whose sum is σ = 33105600. Its totient is φ = 13208832.

The previous prime is 20969513. The next prime is 20969527. The reversal of 20969523 is 32596902.

Added to its reverse (32596902) it gives a triangular number (53566425 = T₁₀₃₅₀).

It is not a de Polignac number, because 20969523 - 2¹⁰ = 20968499 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20969527) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 185515 + ... + 185627.

It is an arithmetic number, because the mean of its divisors is an integer number (827640).

Almost surely, 2^20969523 is an apocalyptic number.

20969523 is a deficient number, since it is larger than the sum of its proper divisors (12136077).

20969523 is a wasteful number, since it uses less digits than its factorization.

20969523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233 (or 224 counting only the distinct ones).

The product of its (nonzero) digits is 29160, while the sum is 36.

The square root of 20969523 is about 4579.2491742643. The cubic root of 20969523 is about 275.7588867787.

Adding to 20969523 its reverse (32596902), we get a triangular number (53566425 = T₁₀₃₅₀).

The spelling of 20969523 in words is "twenty million, nine hundred sixty-nine thousand, five hundred twenty-three".