40398091 has 4 divisors (see below), whose sum is σ = 40411800. Its totient is φ = 40384384.

The previous prime is 40398049. The next prime is 40398109. The reversal of 40398091 is 19089304.

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.

It is a cyclic number.

It is not a de Polignac number, because 40398091 - 2⁹ = 40397579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40398041) 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, 421 + ... + 8998.

It is an arithmetic number, because the mean of its divisors is an integer number (10102950).

Almost surely, 2^40398091 is an apocalyptic number.

40398091 is a deficient number, since it is larger than the sum of its proper divisors (13709).

40398091 is an equidigital number, since it uses as much as digits as its factorization.

40398091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13708.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 40398091 is about 6355.9492603387. The cubic root of 40398091 is about 343.1259896366.

The spelling of 40398091 in words is "forty million, three hundred ninety-eight thousand, ninety-one".