1221499128 has 32 divisors (see below), whose sum is σ = 3061463760. Its totient is φ = 406137600.

The previous prime is 1221499073. The next prime is 1221499133. The reversal of 1221499128 is 8219941221.

It is a congruent 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, 54573 + ... + 73628.

Almost surely, 2^1221499128 is an apocalyptic number.

It is an amenable number.

1221499128 is an abundant number, since it is smaller than the sum of its proper divisors (1839964632).

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

1221499128 is a wasteful number, since it uses less digits than its factorization.

1221499128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128607 (or 128603 counting only the distinct ones).

The product of its digits is 20736, while the sum is 39.

The square root of 1221499128 is about 34949.9517596234. The cubic root of 1221499128 is about 1068.9672184454.

The spelling of 1221499128 in words is "one billion, two hundred twenty-one million, four hundred ninety-nine thousand, one hundred twenty-eight".