1290788945 has 8 divisors (see below), whose sum is σ = 1549349736. Its totient is φ = 1032362496.

The previous prime is 1290788923. The next prime is 1290788951. The reversal of 1290788945 is 5498870921.

It can be written as a sum of positive squares in 4 ways, for example, as 8862529 + 1281926416 = 2977^2 + 35804^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1290788945 - 2¹⁸ = 1290526801 is a prime.

It is a super-2 number, since 2×1290788945² = 3332272201068426050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11072 + ... + 52001.

It is an arithmetic number, because the mean of its divisors is an integer number (193668717).

Almost surely, 2^1290788945 is an apocalyptic number.

It is an amenable number.

1290788945 is a deficient number, since it is larger than the sum of its proper divisors (258560791).

1290788945 is an equidigital number, since it uses as much as digits as its factorization.

1290788945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67171.

The product of its (nonzero) digits is 1451520, while the sum is 53.

The square root of 1290788945 is about 35927.5513359873. The cubic root of 1290788945 is about 1088.8091095332.

The spelling of 1290788945 in words is "one billion, two hundred ninety million, seven hundred eighty-eight thousand, nine hundred forty-five".