1221545432 has 16 divisors (see below), whose sum is σ = 2293064640. Its totient is φ = 610061536.

The previous prime is 1221545383. The next prime is 1221545441. The reversal of 1221545432 is 2345451221.

It is a junction number, because it is equal to n+sod(n) for n = 1221545395 and 1221545404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 81563 + ... + 95370.

It is an arithmetic number, because the mean of its divisors is an integer number (143316540).

Almost surely, 2^1221545432 is an apocalyptic number.

It is an amenable number.

1221545432 is a deficient number, since it is larger than the sum of its proper divisors (1071519208).

1221545432 is a wasteful number, since it uses less digits than its factorization.

1221545432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177802 (or 177798 counting only the distinct ones).

The product of its digits is 9600, while the sum is 29.

The square root of 1221545432 is about 34950.6141863058. The cubic root of 1221545432 is about 1068.9807255727.

Adding to 1221545432 its reverse (2345451221), we get a palindrome (3566996653).

The spelling of 1221545432 in words is "one billion, two hundred twenty-one million, five hundred forty-five thousand, four hundred thirty-two".