1225123521 has 8 divisors (see below), whose sum is σ = 1639526784. Its totient is φ = 813734640.

The previous prime is 1225123519. The next prime is 1225123579. The reversal of 1225123521 is 1253215221.

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

It is not a de Polignac number, because 1225123521 - 2¹ = 1225123519 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1225123491 and 1225123500.

It is not an unprimeable number, because it can be changed into a prime (1225123511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 752646 + ... + 754271.

It is an arithmetic number, because the mean of its divisors is an integer number (204940848).

Almost surely, 2^1225123521 is an apocalyptic number.

It is an amenable number.

1225123521 is a deficient number, since it is larger than the sum of its proper divisors (414403263).

1225123521 is a wasteful number, since it uses less digits than its factorization.

1225123521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1507191.

The product of its digits is 1200, while the sum is 24.

The square root of 1225123521 is about 35001.7645412342. The cubic root of 1225123521 is about 1070.0234428730.

Adding to 1225123521 its reverse (1253215221), we get a palindrome (2478338742).

The spelling of 1225123521 in words is "one billion, two hundred twenty-five million, one hundred twenty-three thousand, five hundred twenty-one".