20670320 has 80 divisors (see below), whose sum is σ = 53246592. Its totient is φ = 7399680.

The previous prime is 20670313. The next prime is 20670337. The reversal of 20670320 is 2307602.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 20670292 and 20670301.

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, 72899 + ... + 73181.

Almost surely, 2^20670320 is an apocalyptic number.

20670320 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 20670320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26623296).

20670320 is an abundant number, since it is smaller than the sum of its proper divisors (32576272).

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

20670320 is a wasteful number, since it uses less digits than its factorization.

20670320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390 (or 384 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 20.

The square root of 20670320 is about 4546.4623610011. The cubic root of 20670320 is about 274.4410464823.

Adding to 20670320 its reverse (2307602), we get a palindrome (22977922).

The spelling of 20670320 in words is "twenty million, six hundred seventy thousand, three hundred twenty".