1221345546 has 32 divisors (see below), whose sum is σ = 2482125120. Its totient is φ = 400557696.

The previous prime is 1221345529. The next prime is 1221345551. The reversal of 1221345546 is 6455431221.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 517000 + ... + 519356.

It is an arithmetic number, because the mean of its divisors is an integer number (77566410).

Almost surely, 2^1221345546 is an apocalyptic number.

1221345546 is an abundant number, since it is smaller than the sum of its proper divisors (1260779574).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221345546 is a wasteful number, since it uses less digits than its factorization.

1221345546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3718.

The product of its digits is 28800, while the sum is 33.

The square root of 1221345546 is about 34947.7545201405. The cubic root of 1221345546 is about 1068.9224153013.

Adding to 1221345546 its reverse (6455431221), we get a palindrome (7676776767).

The spelling of 1221345546 in words is "one billion, two hundred twenty-one million, three hundred forty-five thousand, five hundred forty-six".