20329440 has 96 divisors (see below), whose sum is σ = 65663136. Its totient is φ = 5283840.

The previous prime is 20329417. The next prime is 20329489. The reversal of 20329440 is 4492302.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×20329440² = 826572261427200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 20329440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19164 + ... + 20196.

It is an arithmetic number, because the mean of its divisors is an integer number (683991).

Almost surely, 2^20329440 is an apocalyptic number.

20329440 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 20329440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32831568).

20329440 is an abundant number, since it is smaller than the sum of its proper divisors (45333696).

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

20329440 is a wasteful number, since it uses less digits than its factorization.

20329440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1092 (or 1084 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 20329440 is about 4508.8180269334. The cubic root of 20329440 is about 272.9240486967.

The spelling of 20329440 in words is "twenty million, three hundred twenty-nine thousand, four hundred forty".