1025438861 has 4 divisors (see below), whose sum is σ = 1085758812. Its totient is φ = 965118912.

The previous prime is 1025438857. The next prime is 1025438893. The reversal of 1025438861 is 1688345201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1688345201 = 8467 ⋅199403.

It can be written as a sum of positive squares in 2 ways, for example, as 947469961 + 77968900 = 30781^2 + 8830^2 .

It is a cyclic number.

It is not a de Polignac number, because 1025438861 - 2² = 1025438857 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1025438261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30159950 + ... + 30159983.

It is an arithmetic number, because the mean of its divisors is an integer number (271439703).

Almost surely, 2^1025438861 is an apocalyptic number.

It is an amenable number.

1025438861 is a deficient number, since it is larger than the sum of its proper divisors (60319951).

1025438861 is an equidigital number, since it uses as much as digits as its factorization.

1025438861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60319950.

The product of its (nonzero) digits is 46080, while the sum is 38.

The square root of 1025438861 is about 32022.4743110210. The cubic root of 1025438861 is about 1008.4087156508.

The spelling of 1025438861 in words is "one billion, twenty-five million, four hundred thirty-eight thousand, eight hundred sixty-one".