1221609598 has 32 divisors (see below), whose sum is σ = 2106720000. Its totient is φ = 525424320.

The previous prime is 1221609589. The next prime is 1221609629. The reversal of 1221609598 is 8959061221.

It is a congruent number.

It is an unprimeable number.

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, 583738 + ... + 585826.

It is an arithmetic number, because the mean of its divisors is an integer number (65835000).

Almost surely, 2^1221609598 is an apocalyptic number.

1221609598 is a deficient number, since it is larger than the sum of its proper divisors (885110402).

1221609598 is a wasteful number, since it uses less digits than its factorization.

1221609598 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3520.

The product of its (nonzero) digits is 77760, while the sum is 43.

The square root of 1221609598 is about 34951.5321266465. The cubic root of 1221609598 is about 1068.9994425778. Note that the first 3 decimals are identical.

The spelling of 1221609598 in words is "one billion, two hundred twenty-one million, six hundred nine thousand, five hundred ninety-eight".