1561200071 has 2 divisors, whose sum is σ = 1561200072. Its totient is φ = 1561200070.

The previous prime is 1561200029. The next prime is 1561200101. The reversal of 1561200071 is 1700021651.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1561200071 - 2²² = 1557005767 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1561200671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 780600035 + 780600036.

It is an arithmetic number, because the mean of its divisors is an integer number (780600036).

Almost surely, 2^1561200071 is an apocalyptic number.

1561200071 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561200071 is an equidigital number, since it uses as much as digits as its factorization.

1561200071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 1561200071 is about 39512.0243849894. The cubic root of 1561200071 is about 1160.0753198715.

The spelling of 1561200071 in words is "one billion, five hundred sixty-one million, two hundred thousand, seventy-one".