1664106025 has 6 divisors (see below), whose sum is σ = 2063491502. Its totient is φ = 1331284800.

The previous prime is 1664105987. The next prime is 1664106049. The reversal of 1664106025 is 5206014661.

It can be written as a sum of positive squares in 3 ways, for example, as 1016064 + 1663089961 = 1008^2 + 40781^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1664106025 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 33282096 + ... + 33282145.

Almost surely, 2^1664106025 is an apocalyptic number.

It is an amenable number.

1664106025 is a deficient number, since it is larger than the sum of its proper divisors (399385477).

1664106025 is an equidigital number, since it uses as much as digits as its factorization.

1664106025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66564251 (or 66564246 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 1664106025 is about 40793.4556638684. The cubic root of 1664106025 is about 1185.0235949891.

The spelling of 1664106025 in words is "one billion, six hundred sixty-four million, one hundred six thousand, twenty-five".