31421271520 has 192 divisors, whose sum is σ = 79035264000. Its totient is φ = 11779891200.

The previous prime is 31421271517. The next prime is 31421271523. The reversal of 31421271520 is 2517212413.

It is an interprime number because it is at equal distance from previous prime (31421271517) and next prime (31421271523).

It is a super-2 number, since 2×31421271520² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31421271523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 62968231 + ... + 62968729.

It is an arithmetic number, because the mean of its divisors is an integer number (411642000).

Almost surely, 2^31421271520 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31421271520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39517632000).

31421271520 is an abundant number, since it is smaller than the sum of its proper divisors (47613992480).

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

31421271520 is a wasteful number, since it uses less digits than its factorization.

31421271520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 849 (or 841 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

Adding to 31421271520 its reverse (2517212413), we get a palindrome (33938483933).

The spelling of 31421271520 in words is "thirty-one billion, four hundred twenty-one million, two hundred seventy-one thousand, five hundred twenty".