1561247567 has 16 divisors (see below), whose sum is σ = 1838522880. Its totient is φ = 1310786400.

The previous prime is 1561247563. The next prime is 1561247573. The reversal of 1561247567 is 7657421651.

It is not a de Polignac number, because 1561247567 - 2² = 1561247563 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561247563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 99059 + ... + 113732.

It is an arithmetic number, because the mean of its divisors is an integer number (114907680).

Almost surely, 2^1561247567 is an apocalyptic number.

1561247567 is a deficient number, since it is larger than the sum of its proper divisors (277275313).

1561247567 is a wasteful number, since it uses less digits than its factorization.

1561247567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212854.

The product of its digits is 352800, while the sum is 44.

The square root of 1561247567 is about 39512.6254126450. The cubic root of 1561247567 is about 1160.0870839795.

Subtracting 1561247567 from its reverse (7657421651), we obtain a square (6096174084 = 78078²).

The spelling of 1561247567 in words is "one billion, five hundred sixty-one million, two hundred forty-seven thousand, five hundred sixty-seven".