40517021 has 4 divisors (see below), whose sum is σ = 40729344. Its totient is φ = 40304700.

The previous prime is 40516981. The next prime is 40517023. The reversal of 40517021 is 12071504.

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 40517021 - 2¹⁴ = 40500637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40516984 and 40517002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40517023) 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, 105875 + ... + 106256.

It is an arithmetic number, because the mean of its divisors is an integer number (10182336).

Almost surely, 2^40517021 is an apocalyptic number.

It is an amenable number.

40517021 is a deficient number, since it is larger than the sum of its proper divisors (212323).

40517021 is a wasteful number, since it uses less digits than its factorization.

40517021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212322.

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 40517021 is about 6365.2981862596. The cubic root of 40517021 is about 343.4623751171.

Adding to 40517021 its reverse (12071504), we get a palindrome (52588525).

The spelling of 40517021 in words is "forty million, five hundred seventeen thousand, twenty-one".