20280786 has 32 divisors (see below), whose sum is σ = 41446080. Its totient is φ = 6614784.

The previous prime is 20280781. The next prime is 20280791. The reversal of 20280786 is 68708202.

20280786 is nontrivially palindromic in base 12.

It is an interprime number because it is at equal distance from previous prime (20280781) and next prime (20280791).

It is a super-2 number, since 2×20280786² = 822620561555592, which contains 22 as substring.

20280786 is a Rhonda number in base 8.

It is not an unprimeable number, because it can be changed into a prime (20280781) 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, 86926 + ... + 87158.

It is an arithmetic number, because the mean of its divisors is an integer number (1295190).

Almost surely, 2^20280786 is an apocalyptic number.

20280786 is an abundant number, since it is smaller than the sum of its proper divisors (21165294).

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

20280786 is a wasteful number, since it uses less digits than its factorization.

20280786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 490.

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 20280786 is about 4503.4193675473. The cubic root of 20280786 is about 272.7061470707.

Adding to 20280786 its reverse (68708202), we get a palindrome (88988988).

The spelling of 20280786 in words is "twenty million, two hundred eighty thousand, seven hundred eighty-six".