1561513453 has 2 divisors, whose sum is σ = 1561513454. Its totient is φ = 1561513452.

The previous prime is 1561513451. The next prime is 1561513487. The reversal of 1561513453 is 3543151651.

It is an a-pointer prime, because the next prime (1561513487) can be obtained adding 1561513453 to its sum of digits (34).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 821510244 + 740003209 = 28662^2 + 27203^2 .

It is a cyclic number.

It is not a de Polignac number, because 1561513453 - 2¹ = 1561513451 is a prime.

Together with 1561513451, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1561513451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 780756726 + 780756727.

It is an arithmetic number, because the mean of its divisors is an integer number (780756727).

Almost surely, 2^1561513453 is an apocalyptic number.

It is an amenable number.

1561513453 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561513453 is an equidigital number, since it uses as much as digits as its factorization.

1561513453 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27000, while the sum is 34.

The square root of 1561513453 is about 39515.9898395574. The cubic root of 1561513453 is about 1160.1529358902.

The spelling of 1561513453 in words is "one billion, five hundred sixty-one million, five hundred thirteen thousand, four hundred fifty-three".