20940887 has 8 divisors (see below), whose sum is σ = 22909440. Its totient is φ = 18983160.

The previous prime is 20940877. The next prime is 20940901. The reversal of 20940887 is 78804902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20940887 - 2⁶ = 20940823 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20940887.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20940847) 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, 1658 + ... + 6680.

It is an arithmetic number, because the mean of its divisors is an integer number (2863680).

Almost surely, 2^20940887 is an apocalyptic number.

20940887 is a deficient number, since it is larger than the sum of its proper divisors (1968553).

20940887 is a wasteful number, since it uses less digits than its factorization.

20940887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5413.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 20940887 is about 4576.1213926206. The cubic root of 20940887 is about 275.6333040657.

The spelling of 20940887 in words is "twenty million, nine hundred forty thousand, eight hundred eighty-seven".