20909469 has 16 divisors (see below), whose sum is σ = 32890880. Its totient is φ = 11562480.

The previous prime is 20909453. The next prime is 20909479. The reversal of 20909469 is 96490902.

20909469 = T₃₂₆ + T₃₂₇ + ... + T₅₄₂.

It is not a de Polignac number, because 20909469 - 2⁴ = 20909453 is a prime.

It is a super-2 number, since 2×20909469² = 874411787723922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20909419) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15409 + ... + 16710.

It is an arithmetic number, because the mean of its divisors is an integer number (2055680).

Almost surely, 2^20909469 is an apocalyptic number.

It is an amenable number.

20909469 is a deficient number, since it is larger than the sum of its proper divisors (11981411).

20909469 is a wasteful number, since it uses less digits than its factorization.

20909469 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32160.

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 20909469 is about 4572.6872843001. The cubic root of 20909469 is about 275.4953891563.

The spelling of 20909469 in words is "twenty million, nine hundred nine thousand, four hundred sixty-nine".