9651891 has 4 divisors (see below), whose sum is σ = 12869192. Its totient is φ = 6434592.

The previous prime is 9651877. The next prime is 9651893. The reversal of 9651891 is 1981569.

9651891 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 9651891 - 2²¹ = 7554739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9651893) 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, 1608646 + ... + 1608651.

It is an arithmetic number, because the mean of its divisors is an integer number (3217298).

Almost surely, 2^9651891 is an apocalyptic number.

9651891 is a deficient number, since it is larger than the sum of its proper divisors (3217301).

9651891 is a wasteful number, since it uses less digits than its factorization.

9651891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3217300.

The product of its digits is 19440, while the sum is 39.

The square root of 9651891 is about 3106.7492657117. The cubic root of 9651891 is about 212.9139593858.

The spelling of 9651891 in words is "nine million, six hundred fifty-one thousand, eight hundred ninety-one".