40402420021 has 12 divisors (see below), whose sum is σ = 42665855232. Its totient is φ = 38253470184.

The previous prime is 40402419977. The next prime is 40402420043. The reversal of 40402420021 is 12002420404.

It is not a de Polignac number, because 40402420021 - 2²¹ = 40400322869 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40402420321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 598636 + ... + 662698.

It is an arithmetic number, because the mean of its divisors is an integer number (3555487936).

Almost surely, 2^40402420021 is an apocalyptic number.

It is an amenable number.

40402420021 is a deficient number, since it is larger than the sum of its proper divisors (2263435211).

40402420021 is a wasteful number, since it uses less digits than its factorization.

40402420021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65848 (or 65829 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 19.

Adding to 40402420021 its reverse (12002420404), we get a palindrome (52404840425).

The spelling of 40402420021 in words is "forty billion, four hundred two million, four hundred twenty thousand, twenty-one".