1221525367 has 4 divisors (see below), whose sum is σ = 1232335440. Its totient is φ = 1210715296.

The previous prime is 1221525323. The next prime is 1221525401. The reversal of 1221525367 is 7635251221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7635251221 = 13 ⋅587327017.

It is a cyclic number.

It is not a de Polignac number, because 1221525367 - 2¹⁹ = 1221001079 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221555367) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5404867 + ... + 5405092.

It is an arithmetic number, because the mean of its divisors is an integer number (308083860).

Almost surely, 2^1221525367 is an apocalyptic number.

1221525367 is a deficient number, since it is larger than the sum of its proper divisors (10810073).

1221525367 is a wasteful number, since it uses less digits than its factorization.

1221525367 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10810072.

The product of its digits is 25200, while the sum is 34.

The square root of 1221525367 is about 34950.3271372386. The cubic root of 1221525367 is about 1068.9748725456.

Adding to 1221525367 its reverse (7635251221), we get a palindrome (8856776588).

The spelling of 1221525367 in words is "one billion, two hundred twenty-one million, five hundred twenty-five thousand, three hundred sixty-seven".