20387812 has 12 divisors (see below), whose sum is σ = 36909180. Its totient is φ = 9842336.

The previous prime is 20387803. The next prime is 20387813. The reversal of 20387812 is 21878302.

It can be written as a sum of positive squares in 2 ways, for example, as 17089956 + 3297856 = 4134^2 + 1816^2 .

It is not an unprimeable number, because it can be changed into a prime (20387813) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87763 + ... + 87994.

It is an arithmetic number, because the mean of its divisors is an integer number (3075765).

Almost surely, 2^20387812 is an apocalyptic number.

It is an amenable number.

20387812 is a deficient number, since it is larger than the sum of its proper divisors (16521368).

20387812 is a wasteful number, since it uses less digits than its factorization.

20387812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175790 (or 175788 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 31.

The square root of 20387812 is about 4515.2864803908. The cubic root of 20387812 is about 273.1850150448.

The spelling of 20387812 in words is "twenty million, three hundred eighty-seven thousand, eight hundred twelve".