40991121 has 6 divisors (see below), whose sum is σ = 59209410. Its totient is φ = 27327408.

The previous prime is 40991107. The next prime is 40991141. The reversal of 40991121 is 12119904.

40991121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 32080896 + 8910225 = 5664^2 + 2985^2 .

It is not a de Polignac number, because 40991121 - 2⁶ = 40991057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40991141) 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 5 ways as a sum of consecutive naturals, for example, 2277276 + ... + 2277293.

It is an arithmetic number, because the mean of its divisors is an integer number (9868235).

Almost surely, 2^40991121 is an apocalyptic number.

It is an amenable number.

40991121 is a deficient number, since it is larger than the sum of its proper divisors (18218289).

40991121 is a wasteful number, since it uses less digits than its factorization.

40991121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4554575 (or 4554572 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 27.

The square root of 40991121 is about 6402.4308664756. The cubic root of 40991121 is about 344.7968305982.

The spelling of 40991121 in words is "forty million, nine hundred ninety-one thousand, one hundred twenty-one".