21042131402040 has 128 divisors (see below), whose sum is σ = 72150057538560. Its totient is φ = 4809256233984.

The previous prime is 21042131402023. The next prime is 21042131402111. The reversal of 21042131402040 is 4020413124012.

It is a super-2 number, since 2×21042131402040² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21042131402040.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 9913557 + ... + 11847483.

It is an arithmetic number, because the mean of its divisors is an integer number (563672324520).

Almost surely, 2^{21042131402040} is an apocalyptic number.

21042131402040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21042131402040 is an abundant number, since it is smaller than the sum of its proper divisors (51107926136520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21042131402040 is a wasteful number, since it uses less digits than its factorization.

21042131402040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1946901 (or 1946897 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

Adding to 21042131402040 its reverse (4020413124012), we get a palindrome (25062544526052).

The spelling of 21042131402040 in words is "twenty-one trillion, forty-two billion, one hundred thirty-one million, four hundred two thousand, forty".