1228293921 has 16 divisors (see below), whose sum is σ = 1713731904. Its totient is φ = 781694784.

The previous prime is 1228293917. The next prime is 1228293923. The reversal of 1228293921 is 1293928221.

It is not a de Polignac number, because 1228293921 - 2² = 1228293917 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1228293921.

It is not an unprimeable number, because it can be changed into a prime (1228293923) 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 15 ways as a sum of consecutive naturals, for example, 98511 + ... + 110276.

It is an arithmetic number, because the mean of its divisors is an integer number (107108244).

Almost surely, 2^1228293921 is an apocalyptic number.

It is an amenable number.

1228293921 is a deficient number, since it is larger than the sum of its proper divisors (485437983).

1228293921 is a wasteful number, since it uses less digits than its factorization.

1228293921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208880.

The product of its digits is 31104, while the sum is 39.

The square root of 1228293921 is about 35047.0244243359. The cubic root of 1228293921 is about 1070.9456574240.

The spelling of 1228293921 in words is "one billion, two hundred twenty-eight million, two hundred ninety-three thousand, nine hundred twenty-one".