1221515452 has 12 divisors (see below), whose sum is σ = 2138144400. Its totient is φ = 610617056.

The previous prime is 1221515417. The next prime is 1221515473. The reversal of 1221515452 is 2545151221.

It is a self number, because there is not a number n which added to its sum of digits gives 1221515452.

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, 14248 + ... + 51439.

It is an arithmetic number, because the mean of its divisors is an integer number (178178700).

Almost surely, 2^1221515452 is an apocalyptic number.

It is an amenable number.

1221515452 is a deficient number, since it is larger than the sum of its proper divisors (916628948).

1221515452 is a wasteful number, since it uses less digits than its factorization.

1221515452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70340 (or 70338 counting only the distinct ones).

The product of its digits is 4000, while the sum is 28.

The square root of 1221515452 is about 34950.1852927849. The cubic root of 1221515452 is about 1068.9719802835.

Adding to 1221515452 its reverse (2545151221), we get a palindrome (3766666673).

The spelling of 1221515452 in words is "one billion, two hundred twenty-one million, five hundred fifteen thousand, four hundred fifty-two".