20778025 has 12 divisors (see below), whose sum is σ = 25887232. Its totient is φ = 16543440.

The previous prime is 20778019. The next prime is 20778071. The reversal of 20778025 is 52087702.

It is a de Polignac number, because none of the positive numbers 2^k-20778025 is a prime.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3712 + ... + 7438.

Almost surely, 2^20778025 is an apocalyptic number.

20778025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20778025 is a deficient number, since it is larger than the sum of its proper divisors (5109207).

20778025 is a wasteful number, since it uses less digits than its factorization.

20778025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3960 (or 3955 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 31.

The square root of 20778025 is about 4558.2918949975. The cubic root of 20778025 is about 274.9168894854.

The spelling of 20778025 in words is "twenty million, seven hundred seventy-eight thousand, twenty-five".