31440140340021 has 40 divisors (see below), whose sum is σ = 53677185312960. Its totient is φ = 17965258339392.

The previous prime is 31440140340001. The next prime is 31440140340071. The reversal of 31440140340021 is 12004304104413.

31440140340021 is a `hidden beast` number, since 31 + 440 + 140 + 34 + 0 + 0 + 21 = 666.

It is not a de Polignac number, because 31440140340021 - 2²³ = 31440131951413 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31440140340001) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 18590770 + ... + 20211308.

It is an arithmetic number, because the mean of its divisors is an integer number (1341929632824).

Almost surely, 2^{31440140340021} is an apocalyptic number.

It is an amenable number.

31440140340021 is a deficient number, since it is larger than the sum of its proper divisors (22237044972939).

31440140340021 is a wasteful number, since it uses less digits than its factorization.

31440140340021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1654775 (or 1654766 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

Adding to 31440140340021 its reverse (12004304104413), we get a palindrome (43444444444434).

The spelling of 31440140340021 in words is "thirty-one trillion, four hundred forty billion, one hundred forty million, three hundred forty thousand, twenty-one".