1225521442 has 4 divisors (see below), whose sum is σ = 1838282166. Its totient is φ = 612760720.

The previous prime is 1225521421. The next prime is 1225521463. The reversal of 1225521442 is 2441255221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (1225521421) and next prime (1225521463).

It can be written as a sum of positive squares in only one way, i.e., 782376841 + 443144601 = 27971^2 + 21051^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1225521442.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 306380359 + ... + 306380362.

Almost surely, 2^1225521442 is an apocalyptic number.

1225521442 is a deficient number, since it is larger than the sum of its proper divisors (612760724).

1225521442 is an equidigital number, since it uses as much as digits as its factorization.

1225521442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 612760723.

The product of its digits is 6400, while the sum is 28.

The square root of 1225521442 is about 35007.4483788807. The cubic root of 1225521442 is about 1070.1392784605.

Adding to 1225521442 its reverse (2441255221), we get a palindrome (3666776663).

The spelling of 1225521442 in words is "one billion, two hundred twenty-five million, five hundred twenty-one thousand, four hundred forty-two".