1025636778 has 12 divisors (see below), whose sum is σ = 2222213058. Its totient is φ = 341878920.

The previous prime is 1025636749. The next prime is 1025636779. The reversal of 1025636778 is 8776365201.

1025636778 is a `hidden beast` number, since 1 + 0 + 2 + 5 + 636 + 7 + 7 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1024832169 + 804609 = 32013^2 + 897^2 .

It is not an unprimeable number, because it can be changed into a prime (1025636779) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 28489893 + ... + 28489928.

Almost surely, 2^1025636778 is an apocalyptic number.

1025636778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1025636778 is an abundant number, since it is smaller than the sum of its proper divisors (1196576280).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1025636778 is a wasteful number, since it uses less digits than its factorization.

1025636778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56979829 (or 56979826 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 45.

The square root of 1025636778 is about 32025.5644446745. The cubic root of 1025636778 is about 1008.4735881643.

The spelling of 1025636778 in words is "one billion, twenty-five million, six hundred thirty-six thousand, seven hundred seventy-eight".