1225144521 has 48 divisors (see below), whose sum is σ = 1913999360. Its totient is φ = 782246160.

The previous prime is 1225144477. The next prime is 1225144537. The reversal of 1225144521 is 1254415221.

It is a happy number.

1225144521 is a `hidden beast` number, since 122 + 5 + 14 + 4 + 521 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-1225144521 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1225144021) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 775110 + ... + 776688.

Almost surely, 2^1225144521 is an apocalyptic number.

It is an amenable number.

1225144521 is a deficient number, since it is larger than the sum of its proper divisors (688854839).

1225144521 is a wasteful number, since it uses less digits than its factorization.

1225144521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1728 (or 1716 counting only the distinct ones).

The product of its digits is 3200, while the sum is 27.

The square root of 1225144521 is about 35002.0645248248. The cubic root of 1225144521 is about 1070.0295566413.

Adding to 1225144521 its reverse (1254415221), we get a palindrome (2479559742).

The spelling of 1225144521 in words is "one billion, two hundred twenty-five million, one hundred forty-four thousand, five hundred twenty-one".