1225513561 has 16 divisors (see below), whose sum is σ = 1318680000. Its totient is φ = 1134770688.

The previous prime is 1225513559. The next prime is 1225513567. The reversal of 1225513561 is 1653155221.

It is a cyclic number.

It is not a de Polignac number, because 1225513561 - 2¹ = 1225513559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1225513567) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 618270 + ... + 620248.

It is an arithmetic number, because the mean of its divisors is an integer number (82417500).

Almost surely, 2^1225513561 is an apocalyptic number.

It is an amenable number.

1225513561 is a deficient number, since it is larger than the sum of its proper divisors (93166439).

1225513561 is a wasteful number, since it uses less digits than its factorization.

1225513561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2568.

The product of its digits is 9000, while the sum is 31.

The square root of 1225513561 is about 35007.3358169399. The cubic root of 1225513561 is about 1070.1369845292.

Adding to 1225513561 its reverse (1653155221), we get a palindrome (2878668782).

The spelling of 1225513561 in words is "one billion, two hundred twenty-five million, five hundred thirteen thousand, five hundred sixty-one".