1228621945 has 4 divisors (see below), whose sum is σ = 1474346340. Its totient is φ = 982897552.

The previous prime is 1228621931. The next prime is 1228621987. The reversal of 1228621945 is 5491268221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 291282489 + 937339456 = 17067^2 + 30616^2 .

It is a cyclic number.

It is not a de Polignac number, because 1228621945 - 2⁵ = 1228621913 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1228621898 and 1228621907.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122862190 + ... + 122862199.

It is an arithmetic number, because the mean of its divisors is an integer number (368586585).

Almost surely, 2^1228621945 is an apocalyptic number.

It is an amenable number.

1228621945 is a deficient number, since it is larger than the sum of its proper divisors (245724395).

1228621945 is an equidigital number, since it uses as much as digits as its factorization.

1228621945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245724394.

The product of its digits is 69120, while the sum is 40.

The square root of 1228621945 is about 35051.7038815519. The cubic root of 1228621945 is about 1071.0409833079.

The spelling of 1228621945 in words is "one billion, two hundred twenty-eight million, six hundred twenty-one thousand, nine hundred forty-five".