20387766 has 16 divisors (see below), whose sum is σ = 46600704. Its totient is φ = 5825064.

The previous prime is 20387761. The next prime is 20387771. The reversal of 20387766 is 66778302.

It is an interprime number because it is at equal distance from previous prime (20387761) and next prime (20387771).

It is a super-2 number, since 2×20387766² = 831322004941512, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20387761) 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, 242670 + ... + 242753.

It is an arithmetic number, because the mean of its divisors is an integer number (2912544).

Almost surely, 2^20387766 is an apocalyptic number.

20387766 is an abundant number, since it is smaller than the sum of its proper divisors (26212938).

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

20387766 is a wasteful number, since it uses less digits than its factorization.

20387766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485435.

The product of its (nonzero) digits is 84672, while the sum is 39.

The square root of 20387766 is about 4515.2813865805. The cubic root of 20387766 is about 273.1848095868.

The spelling of 20387766 in words is "twenty million, three hundred eighty-seven thousand, seven hundred sixty-six".