1553668481 has 2 divisors, whose sum is σ = 1553668482. Its totient is φ = 1553668480.

The previous prime is 1553668477. The next prime is 1553668531. The reversal of 1553668481 is 1848663551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 994771600 + 558896881 = 31540^2 + 23641^2 .

It is a cyclic number.

It is not a de Polignac number, because 1553668481 - 2² = 1553668477 is a prime.

It is a super-2 number, since 2×1553668481² = 4827771497705694722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1553608481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 776834240 + 776834241.

It is an arithmetic number, because the mean of its divisors is an integer number (776834241).

Almost surely, 2^1553668481 is an apocalyptic number.

It is an amenable number.

1553668481 is a deficient number, since it is larger than the sum of its proper divisors (1).

1553668481 is an equidigital number, since it uses as much as digits as its factorization.

1553668481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 691200, while the sum is 47.

The square root of 1553668481 is about 39416.6015912077. The cubic root of 1553668481 is about 1158.2068214584.

The spelling of 1553668481 in words is "one billion, five hundred fifty-three million, six hundred sixty-eight thousand, four hundred eighty-one".