20079840 has 96 divisors (see below), whose sum is σ = 69019776. Its totient is φ = 4866560.

The previous prime is 20079821. The next prime is 20079841. The reversal of 20079840 is 4897002.

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

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 20079798 and 20079807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20079841) 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, 3379 + ... + 7181.

It is an arithmetic number, because the mean of its divisors is an integer number (718956).

Almost surely, 2^20079840 is an apocalyptic number.

20079840 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 20079840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34509888).

20079840 is an abundant number, since it is smaller than the sum of its proper divisors (48939936).

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

20079840 is a wasteful number, since it uses less digits than its factorization.

20079840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3832 (or 3824 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 20079840 is about 4481.0534475723. The cubic root of 20079840 is about 271.8024805920.

The spelling of 20079840 in words is "twenty million, seventy-nine thousand, eight hundred forty".