20842690 has 16 divisors (see below), whose sum is σ = 40927680. Its totient is φ = 7579120.

The previous prime is 20842687. The next prime is 20842691. The reversal of 20842690 is 9624802.

It is a super-2 number, since 2×20842690² = 868835452872200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20842691) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94630 + ... + 94849.

It is an arithmetic number, because the mean of its divisors is an integer number (2557980).

Almost surely, 2^20842690 is an apocalyptic number.

20842690 is a deficient number, since it is larger than the sum of its proper divisors (20084990).

20842690 is a wasteful number, since it uses less digits than its factorization.

20842690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189497.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 20842690 is about 4565.3795022977. The cubic root of 20842690 is about 275.2017912860.

It can be divided in two parts, 2084 and 2690, that added together give a palindrome (4774).

The spelling of 20842690 in words is "twenty million, eight hundred forty-two thousand, six hundred ninety".