20778087 has 16 divisors (see below), whose sum is σ = 30521088. Its totient is φ = 12468480.

The previous prime is 20778083. The next prime is 20778113. The reversal of 20778087 is 78087702.

It is not a de Polignac number, because 20778087 - 2² = 20778083 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20778083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 343 + ... + 6455.

It is an arithmetic number, because the mean of its divisors is an integer number (1907568).

Almost surely, 2^20778087 is an apocalyptic number.

20778087 is a deficient number, since it is larger than the sum of its proper divisors (9743001).

20778087 is a wasteful number, since it uses less digits than its factorization.

20778087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6230.

The product of its (nonzero) digits is 43904, while the sum is 39.

The square root of 20778087 is about 4558.2986957855. The cubic root of 20778087 is about 274.9171629286.

The spelling of 20778087 in words is "twenty million, seven hundred seventy-eight thousand, eighty-seven".