1665297625 has 8 divisors (see below), whose sum is σ = 2078291592. Its totient is φ = 1332238000.

The previous prime is 1665297619. The next prime is 1665297629. The reversal of 1665297625 is 5267925661.

It can be written as a sum of positive squares in 4 ways, for example, as 4761 + 1665292864 = 69^2 + 40808^2 .

It is not a de Polignac number, because 1665297625 - 2¹⁵ = 1665264857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1665297629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6661066 + ... + 6661315.

It is an arithmetic number, because the mean of its divisors is an integer number (259786449).

Almost surely, 2^1665297625 is an apocalyptic number.

It is an amenable number.

1665297625 is a deficient number, since it is larger than the sum of its proper divisors (412993967).

1665297625 is an equidigital number, since it uses as much as digits as its factorization.

1665297625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13322396 (or 13322386 counting only the distinct ones).

The product of its digits is 1360800, while the sum is 49.

The square root of 1665297625 is about 40808.0583341085. The cubic root of 1665297625 is about 1185.3063768923.

The spelling of 1665297625 in words is "one billion, six hundred sixty-five million, two hundred ninety-seven thousand, six hundred twenty-five".