820861025 has 12 divisors (see below), whose sum is σ = 1025194800. Its totient is φ = 651961680.

The previous prime is 820861003. The next prime is 820861043. The reversal of 820861025 is 520168028.

It is not a de Polignac number, because 820861025 - 2⁸ = 820860769 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 820860982 and 820861000.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 114635 + ... + 121584.

It is an arithmetic number, because the mean of its divisors is an integer number (85432900).

Almost surely, 2^820861025 is an apocalyptic number.

It is an amenable number.

820861025 is a deficient number, since it is larger than the sum of its proper divisors (204333775).

820861025 is a wasteful number, since it uses less digits than its factorization.

820861025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236368 (or 236363 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 32.

The square root of 820861025 is about 28650.6723306801. The cubic root of 820861025 is about 936.3176537844.

The spelling of 820861025 in words is "eight hundred twenty million, eight hundred sixty-one thousand, twenty-five".