1601531 has 4 divisors (see below), whose sum is σ = 1604064. Its totient is φ = 1599000.

The previous prime is 1601527. The next prime is 1601533. The reversal of 1601531 is 1351061.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1601531 - 2² = 1601527 is a prime.

It is a super-2 number, since 2×1601531² = 5129803087922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1601533) 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, 581 + ... + 1881.

It is an arithmetic number, because the mean of its divisors is an integer number (401016).

2^1601531 is an apocalyptic number.

1601531 is a deficient number, since it is larger than the sum of its proper divisors (2533).

1601531 is a wasteful number, since it uses less digits than its factorization.

1601531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2532.

The product of its (nonzero) digits is 90, while the sum is 17.

The square root of 1601531 is about 1265.5161002532. The cubic root of 1601531 is about 116.9980032289.

Adding to 1601531 its reverse (1351061), we get a palindrome (2952592).

The spelling of 1601531 in words is "one million, six hundred one thousand, five hundred thirty-one".