1245878209 has 9 divisors (see below), whose sum is σ = 1274647521. Its totient is φ = 1217746500.

The previous prime is 1245878177. The next prime is 1245878219. The reversal of 1245878209 is 9028785421.

The square root of 1245878209 is 35297.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 1245878209 - 2⁵ = 1245878177 is a prime.

It is a super-2 number, since 2×1245878209² = 3104425023322095362, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1245878219) 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 8 ways as a sum of consecutive naturals, for example, 1658584 + ... + 1659334.

Almost surely, 2^1245878209 is an apocalyptic number.

1245878209 is the 35297-th square number.

1245878209 is the 17649-th centered octagonal number.

It is an amenable number.

1245878209 is a deficient number, since it is larger than the sum of its proper divisors (28769312).

1245878209 is an frugal number, since it uses more digits than its factorization.

1245878209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1596 (or 798 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 46.

The cubic root of 1245878209 is about 1076.0320239521.

The spelling of 1245878209 in words is "one billion, two hundred forty-five million, eight hundred seventy-eight thousand, two hundred nine".