40126021 has 4 divisors (see below), whose sum is σ = 43212652. Its totient is φ = 37039392.

The previous prime is 40126013. The next prime is 40126027. The reversal of 40126021 is 12062104.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4901796 + 35224225 = 2214^2 + 5935^2 .

It is not a de Polignac number, because 40126021 - 2³ = 40126013 is a prime.

It is a super-2 number, since 2×40126021² = 3220195122584882, 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 = 40125986 and 40126004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40126027) 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, 1543296 + ... + 1543321.

It is an arithmetic number, because the mean of its divisors is an integer number (10803163).

Almost surely, 2^40126021 is an apocalyptic number.

It is an amenable number.

40126021 is a deficient number, since it is larger than the sum of its proper divisors (3086631).

40126021 is a wasteful number, since it uses less digits than its factorization.

40126021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3086630.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 40126021 is about 6334.5103204589. The cubic root of 40126021 is about 342.3539676167.

Adding to 40126021 its reverse (12062104), we get a palindrome (52188125).

The spelling of 40126021 in words is "forty million, one hundred twenty-six thousand, twenty-one".