40011921 has 16 divisors (see below), whose sum is σ = 59660800. Its totient is φ = 26501904.

The previous prime is 40011889. The next prime is 40011943. The reversal of 40011921 is 12911004.

It is not a de Polignac number, because 40011921 - 2⁵ = 40011889 is a prime.

It is a super-2 number, since 2×40011921² = 3201907644220482, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40011894 and 40011903.

It is not an unprimeable number, because it can be changed into a prime (40011991) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 481 + ... + 8958.

It is an arithmetic number, because the mean of its divisors is an integer number (3728800).

Almost surely, 2^40011921 is an apocalyptic number.

It is an amenable number.

40011921 is a deficient number, since it is larger than the sum of its proper divisors (19648879).

40011921 is a wasteful number, since it uses less digits than its factorization.

40011921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9605 (or 9599 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 40011921 is about 6325.4976879294. The cubic root of 40011921 is about 342.0291603329.

Adding to 40011921 its reverse (12911004), we get a palindrome (52922925).

It can be divided in two parts, 400 and 11921, that added together give a palindrome (12321).

The spelling of 40011921 in words is "forty million, eleven thousand, nine hundred twenty-one".