40390491 has 4 divisors (see below), whose sum is σ = 53853992. Its totient is φ = 26926992.

The previous prime is 40390463. The next prime is 40390513. The reversal of 40390491 is 19409304.

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

It is not a de Polignac number, because 40390491 - 2¹³ = 40382299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40390411) 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, 6731746 + ... + 6731751.

It is an arithmetic number, because the mean of its divisors is an integer number (13463498).

Almost surely, 2^40390491 is an apocalyptic number.

40390491 is a deficient number, since it is larger than the sum of its proper divisors (13463501).

40390491 is a wasteful number, since it uses less digits than its factorization.

40390491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13463500.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 40390491 is about 6355.3513671551. The cubic root of 40390491 is about 343.1044711193.

Adding to 40390491 its reverse (19409304), we get a palindrome (59799795).

The spelling of 40390491 in words is "forty million, three hundred ninety thousand, four hundred ninety-one".