1025640042 has 64 divisors (see below), whose sum is σ = 2481684480. Its totient is φ = 276341184.

The previous prime is 1025640041. The next prime is 1025640097. The reversal of 1025640042 is 2400465201.

It is a junction number, because it is equal to n+sod(n) for n = 1025639994 and 1025640021.

It is not an unprimeable number, because it can be changed into a prime (1025640041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42583 + ... + 62165.

It is an arithmetic number, because the mean of its divisors is an integer number (38776320).

Almost surely, 2^1025640042 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1025640042, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1240842240).

1025640042 is an abundant number, since it is smaller than the sum of its proper divisors (1456044438).

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

1025640042 is a wasteful number, since it uses less digits than its factorization.

1025640042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19667.

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 1025640042 is about 32025.6154039232. The cubic root of 1025640042 is about 1008.4746579564.

The spelling of 1025640042 in words is "one billion, twenty-five million, six hundred forty thousand, forty-two".