20778125 has 24 divisors (see below), whose sum is σ = 26638920. Its totient is φ = 16200000.

The previous prime is 20778113. The next prime is 20778139. The reversal of 20778125 is 52187702.

It can be written as a sum of positive squares in 12 ways, for example, as 20232004 + 546121 = 4498^2 + 739^2 .

It is not a de Polignac number, because 20778125 - 2¹⁰ = 20777101 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20778091 and 20778100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 190571 + ... + 190679.

It is an arithmetic number, because the mean of its divisors is an integer number (1109955).

Almost surely, 2^20778125 is an apocalyptic number.

20778125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20778125 is a deficient number, since it is larger than the sum of its proper divisors (5860795).

20778125 is an frugal number, since it uses more digits than its factorization.

20778125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195 (or 175 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 32.

The square root of 20778125 is about 4558.3028640054. The cubic root of 20778125 is about 274.9173305226.

The spelling of 20778125 in words is "twenty million, seven hundred seventy-eight thousand, one hundred twenty-five".