40510021 has 4 divisors (see below), whose sum is σ = 40801600. Its totient is φ = 40218444.

The previous prime is 40510007. The next prime is 40510037. The reversal of 40510021 is 12001504.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40510021 - 2¹⁵ = 40477253 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40509983 and 40510010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40510051) 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, 145581 + ... + 145858.

It is an arithmetic number, because the mean of its divisors is an integer number (10200400).

Almost surely, 2^40510021 is an apocalyptic number.

It is an amenable number.

40510021 is a deficient number, since it is larger than the sum of its proper divisors (291579).

40510021 is a wasteful number, since it uses less digits than its factorization.

40510021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291578.

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 40510021 is about 6364.7483060998. The cubic root of 40510021 is about 343.4425943350.

Adding to 40510021 its reverse (12001504), we get a palindrome (52511525).

The spelling of 40510021 in words is "forty million, five hundred ten thousand, twenty-one".