20857782 has 32 divisors (see below), whose sum is σ = 47905920. Its totient is φ = 5987520.

The previous prime is 20857777. The next prime is 20857783. The reversal of 20857782 is 28775802.

It is a self number, because there is not a number n which added to its sum of digits gives 20857782.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20857783) 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, 7063 + ... + 9570.

It is an arithmetic number, because the mean of its divisors is an integer number (1497060).

Almost surely, 2^20857782 is an apocalyptic number.

20857782 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

20857782 is an abundant number, since it is smaller than the sum of its proper divisors (27048138).

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

20857782 is a wasteful number, since it uses less digits than its factorization.

20857782 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16668.

The product of its (nonzero) digits is 62720, while the sum is 39.

The square root of 20857782 is about 4567.0320778379. The cubic root of 20857782 is about 275.2681989549.

The spelling of 20857782 in words is "twenty million, eight hundred fifty-seven thousand, seven hundred eighty-two".