1561237 has 4 divisors (see below), whose sum is σ = 1575936. Its totient is φ = 1546540.

The previous prime is 1561213. The next prime is 1561243. The reversal of 1561237 is 7321651.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 7321651 = 587 ⋅12473.

It is a cyclic number.

It is not a de Polignac number, because 1561237 - 2¹⁵ = 1528469 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7189 + ... + 7402.

It is an arithmetic number, because the mean of its divisors is an integer number (393984).

2^1561237 is an apocalyptic number.

It is an amenable number.

1561237 is a deficient number, since it is larger than the sum of its proper divisors (14699).

1561237 is a wasteful number, since it uses less digits than its factorization.

1561237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14698.

The product of its digits is 1260, while the sum is 25.

The square root of 1561237 is about 1249.4946978679. The cubic root of 1561237 is about 116.0084466699.

Adding to 1561237 its reverse (7321651), we get a palindrome (8882888).

The spelling of 1561237 in words is "one million, five hundred sixty-one thousand, two hundred thirty-seven".