1220725061 has 4 divisors (see below), whose sum is σ = 1220829324. Its totient is φ = 1220620800.

The previous prime is 1220725049. The next prime is 1220725067. The reversal of 1220725061 is 1605270221.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1605270221 = 127 ⋅12639923.

It can be written as a sum of positive squares in 2 ways, for example, as 452880961 + 767844100 = 21281^2 + 27710^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220725061 - 2¹⁸ = 1220462917 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1220725061.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220725067) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31970 + ... + 58851.

It is an arithmetic number, because the mean of its divisors is an integer number (305207331).

Almost surely, 2^1220725061 is an apocalyptic number.

It is an amenable number.

1220725061 is a deficient number, since it is larger than the sum of its proper divisors (104263).

1220725061 is an equidigital number, since it uses as much as digits as its factorization.

1220725061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104262.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 1220725061 is about 34938.8760695017. The cubic root of 1220725061 is about 1068.7413683468.

Adding to 1220725061 its reverse (1605270221), we get a palindrome (2825995282).

The spelling of 1220725061 in words is "one billion, two hundred twenty million, seven hundred twenty-five thousand, sixty-one".