1221604572 has 24 divisors (see below), whose sum is σ = 2855875456. Its totient is φ = 406420848.

The previous prime is 1221604537. The next prime is 1221604591. The reversal of 1221604572 is 2754061221.

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 7 ways as a sum of consecutive naturals, for example, 91048 + ... + 103599.

Almost surely, 2^1221604572 is an apocalyptic number.

1221604572 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1221604572 is an abundant number, since it is smaller than the sum of its proper divisors (1634270884).

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

1221604572 is a wasteful number, since it uses less digits than its factorization.

1221604572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195177 (or 195175 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 1221604572 is about 34951.4602270063. The cubic root of 1221604572 is about 1068.9979765343.

Adding to 1221604572 its reverse (2754061221), we get a palindrome (3975665793).

The spelling of 1221604572 in words is "one billion, two hundred twenty-one million, six hundred four thousand, five hundred seventy-two".