1228007561 has 4 divisors (see below), whose sum is σ = 1339644624. Its totient is φ = 1116370500.

The previous prime is 1228007537. The next prime is 1228007567. The reversal of 1228007561 is 1657008221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1228007561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1228007567) 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 3 ways as a sum of consecutive naturals, for example, 55818515 + ... + 55818536.

It is an arithmetic number, because the mean of its divisors is an integer number (334911156).

Almost surely, 2^1228007561 is an apocalyptic number.

1228007561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1228007561 is a deficient number, since it is larger than the sum of its proper divisors (111637063).

1228007561 is a wasteful number, since it uses less digits than its factorization.

1228007561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111637062.

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 1228007561 is about 35042.9388179702. The cubic root of 1228007561 is about 1070.8624254904.

The spelling of 1228007561 in words is "one billion, two hundred twenty-eight million, seven thousand, five hundred sixty-one".