1221522533 has 16 divisors (see below), whose sum is σ = 1525910400. Its totient is φ = 949977600.

The previous prime is 1221522517. The next prime is 1221522541. The reversal of 1221522533 is 3352251221.

It is a happy number.

It is not a de Polignac number, because 1221522533 - 2⁴ = 1221522517 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221522563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24893 + ... + 55341.

It is an arithmetic number, because the mean of its divisors is an integer number (95369400).

Almost surely, 2^1221522533 is an apocalyptic number.

It is an amenable number.

1221522533 is a deficient number, since it is larger than the sum of its proper divisors (304387867).

1221522533 is a wasteful number, since it uses less digits than its factorization.

1221522533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30988.

The product of its digits is 3600, while the sum is 26.

The square root of 1221522533 is about 34950.2865939609. The cubic root of 1221522533 is about 1068.9740458532.

Adding to 1221522533 its reverse (3352251221), we get a palindrome (4573773754).

The spelling of 1221522533 in words is "one billion, two hundred twenty-one million, five hundred twenty-two thousand, five hundred thirty-three".