9921151 has 4 divisors (see below), whose sum is σ = 9927904. Its totient is φ = 9914400.

The previous prime is 9921137. The next prime is 9921167. The reversal of 9921151 is 1511299.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1511299 = 457 ⋅3307.

It is a cyclic number.

It is not a de Polignac number, because 9921151 - 2²³ = 1532543 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 (9921851) 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, 135 + ... + 4456.

It is an arithmetic number, because the mean of its divisors is an integer number (2481976).

Almost surely, 2^9921151 is an apocalyptic number.

9921151 is a deficient number, since it is larger than the sum of its proper divisors (6753).

9921151 is a wasteful number, since it uses less digits than its factorization.

9921151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6752.

The product of its digits is 810, while the sum is 28.

The square root of 9921151 is about 3149.7858657375. The cubic root of 9921151 is about 214.8757241047.

The spelling of 9921151 in words is "nine million, nine hundred twenty-one thousand, one hundred fifty-one".