40056821 has 16 divisors (see below), whose sum is σ = 46792704. Its totient is φ = 33582384.

The previous prime is 40056767. The next prime is 40056833. The reversal of 40056821 is 12865004.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40056821 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40056421) 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, 104396 + ... + 104778.

It is an arithmetic number, because the mean of its divisors is an integer number (2924544).

Almost surely, 2^40056821 is an apocalyptic number.

It is an amenable number.

40056821 is a deficient number, since it is larger than the sum of its proper divisors (6735883).

40056821 is a wasteful number, since it uses less digits than its factorization.

40056821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 40056821 is about 6329.0458206589. The cubic root of 40056821 is about 342.1570502891.

The spelling of 40056821 in words is "forty million, fifty-six thousand, eight hundred twenty-one".