7531661 has 4 divisors (see below), whose sum is σ = 7537152. Its totient is φ = 7526172.

The previous prime is 7531651. The next prime is 7531681. The reversal of 7531661 is 1661357.

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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1661357 = 787 ⋅2111.

It is a cyclic number.

It is not a de Polignac number, because 7531661 - 2⁶ = 7531597 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 (7531651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1286 + ... + 4088.

It is an arithmetic number, because the mean of its divisors is an integer number (1884288).

Almost surely, 2^7531661 is an apocalyptic number.

It is an amenable number.

7531661 is a deficient number, since it is larger than the sum of its proper divisors (5491).

7531661 is a wasteful number, since it uses less digits than its factorization.

7531661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5490.

The product of its digits is 3780, while the sum is 29.

The square root of 7531661 is about 2744.3871811390. The cubic root of 7531661 is about 196.0184367635.

It can be divided in two parts, 7531 and 661, that added together give a 13-th power (8192 = 2¹³).

The spelling of 7531661 in words is "seven million, five hundred thirty-one thousand, six hundred sixty-one".