20269440 has 320 divisors, whose sum is σ = 79976160. Its totient is φ = 4866048.

The previous prime is 20269429. The next prime is 20269441. The reversal of 20269440 is 4496202.

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20269441) 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, 881269 + ... + 881291.

Almost surely, 2^20269440 is an apocalyptic number.

20269440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20269440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39988080).

20269440 is an abundant number, since it is smaller than the sum of its proper divisors (59706720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20269440 is a wasteful number, since it uses less digits than its factorization.

20269440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71 (or 50 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 20269440 is about 4502.1594818487. The cubic root of 20269440 is about 272.6552828172.

The spelling of 20269440 in words is "twenty million, two hundred sixty-nine thousand, four hundred forty".