1025640018 has 48 divisors (see below), whose sum is σ = 2409091776. Its totient is φ = 313480800.

The previous prime is 1025640017. The next prime is 1025640041. The reversal of 1025640018 is 8100465201.

1025640018 is a `hidden beast` number, since 1 + 0 + 2 + 5 + 640 + 0 + 18 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 1025639973 and 1025640000.

It is not an unprimeable number, because it can be changed into a prime (1025640017) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20821 + ... + 49847.

It is an arithmetic number, because the mean of its divisors is an integer number (50189412).

Almost surely, 2^1025640018 is an apocalyptic number.

1025640018 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1025640018, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1204545888).

1025640018 is an abundant number, since it is smaller than the sum of its proper divisors (1383451758).

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

1025640018 is a wasteful number, since it uses less digits than its factorization.

1025640018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29199 (or 29196 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 1025640018 is about 32025.6150292231. The cubic root of 1025640018 is about 1008.4746500903.

The spelling of 1025640018 in words is "one billion, twenty-five million, six hundred forty thousand, eighteen".