21040031407 has 4 divisors (see below), whose sum is σ = 21040367040. Its totient is φ = 21039695776.

The previous prime is 21040031393. The next prime is 21040031429. The reversal of 21040031407 is 70413004012.

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

It is a cyclic number.

It is not a de Polignac number, because 21040031407 - 2¹¹ = 21040029359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21040031447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42682 + ... + 209527.

It is an arithmetic number, because the mean of its divisors is an integer number (5260091760).

Almost surely, 2^21040031407 is an apocalyptic number.

21040031407 is a deficient number, since it is larger than the sum of its proper divisors (335633).

21040031407 is an equidigital number, since it uses as much as digits as its factorization.

21040031407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335632.

The product of its (nonzero) digits is 672, while the sum is 22.

Adding to 21040031407 its reverse (70413004012), we get a palindrome (91453035419).

The spelling of 21040031407 in words is "twenty-one billion, forty million, thirty-one thousand, four hundred seven".