20807280 has 300 divisors, whose sum is σ = 82371960. Its totient is φ = 4852224.

The previous prime is 20807273. The next prime is 20807287. The reversal of 20807280 is 8270802.

It is an interprime number because it is at equal distance from previous prime (20807273) and next prime (20807287).

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 (20807287) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 1095111 + ... + 1095129.

Almost surely, 2^20807280 is an apocalyptic number.

20807280 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 20807280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41185980).

20807280 is an abundant number, since it is smaller than the sum of its proper divisors (61564680).

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

20807280 is a wasteful number, since it uses less digits than its factorization.

20807280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70 (or 42 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 20807280 is about 4561.4997533706. The cubic root of 20807280 is about 275.0458546125.

The spelling of 20807280 in words is "twenty million, eight hundred seven thousand, two hundred eighty".