9491551 has 4 divisors (see below), whose sum is σ = 9533592. Its totient is φ = 9449512.

The previous prime is 9491543. The next prime is 9491561. The reversal of 9491551 is 1551949.

It is a happy number.

9491551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1551949 = 7 ⋅221707.

It is a cyclic number.

It is not a de Polignac number, because 9491551 - 2³ = 9491543 is a prime.

It is a Duffinian number.

9491551 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9491561) 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, 20680 + ... + 21133.

It is an arithmetic number, because the mean of its divisors is an integer number (2383398).

Almost surely, 2^9491551 is an apocalyptic number.

9491551 is a deficient number, since it is larger than the sum of its proper divisors (42041).

9491551 is a wasteful number, since it uses less digits than its factorization.

9491551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42040.

The product of its digits is 8100, while the sum is 34.

The square root of 9491551 is about 3080.8360878177. The cubic root of 9491551 is about 211.7283737945.

It can be divided in two parts, 949 and 1551, that added together give a square (2500 = 50²).

The spelling of 9491551 in words is "nine million, four hundred ninety-one thousand, five hundred fifty-one".