1561322031 has 16 divisors (see below), whose sum is σ = 2103859968. Its totient is φ = 1029888000.

The previous prime is 1561322003. The next prime is 1561322033. The reversal of 1561322031 is 1302231651.

It is not a de Polignac number, because 1561322031 - 2¹³ = 1561313839 is a prime.

It is a super-2 number, since 2×1561322031² = 4875452968971929922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1561321992 and 1561322010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561322033) 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, 109716 + ... + 123126.

It is an arithmetic number, because the mean of its divisors is an integer number (131491248).

Almost surely, 2^1561322031 is an apocalyptic number.

1561322031 is a deficient number, since it is larger than the sum of its proper divisors (542537937).

1561322031 is a wasteful number, since it uses less digits than its factorization.

1561322031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13822.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 1561322031 is about 39513.5676825062. The cubic root of 1561322031 is about 1160.1055272111.

Adding to 1561322031 its reverse (1302231651), we get a palindrome (2863553682).

The spelling of 1561322031 in words is "one billion, five hundred sixty-one million, three hundred twenty-two thousand, thirty-one".