1221352505 has 8 divisors (see below), whose sum is σ = 1551836232. Its totient is φ = 919606528.

The previous prime is 1221352501. The next prime is 1221352513. The reversal of 1221352505 is 5052531221.

It can be written as a sum of positive squares in 4 ways, for example, as 325008784 + 896343721 = 18028^2 + 29939^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221352505 - 2² = 1221352501 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221352501) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7184342 + ... + 7184511.

It is an arithmetic number, because the mean of its divisors is an integer number (193979529).

Almost surely, 2^1221352505 is an apocalyptic number.

It is an amenable number.

1221352505 is a deficient number, since it is larger than the sum of its proper divisors (330483727).

1221352505 is a wasteful number, since it uses less digits than its factorization.

1221352505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14368875.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 1221352505 is about 34947.8540829047. The cubic root of 1221352505 is about 1068.9244454712.

Adding to 1221352505 its reverse (5052531221), we get a palindrome (6273883726).

The spelling of 1221352505 in words is "one billion, two hundred twenty-one million, three hundred fifty-two thousand, five hundred five".