31321011021 has 16 divisors (see below), whose sum is σ = 44238743424. Its totient is φ = 19643134464.

The previous prime is 31321011019. The next prime is 31321011049. The reversal of 31321011021 is 12011012313.

It is a happy number.

It is not a de Polignac number, because 31321011021 - 2¹ = 31321011019 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31321011061) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34705 + ... + 252678.

It is an arithmetic number, because the mean of its divisors is an integer number (2764921464).

Almost surely, 2^31321011021 is an apocalyptic number.

It is an amenable number.

31321011021 is a deficient number, since it is larger than the sum of its proper divisors (12917732403).

31321011021 is a wasteful number, since it uses less digits than its factorization.

31321011021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289540.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 31321011021 its reverse (12011012313), we get a palindrome (43332023334).

The spelling of 31321011021 in words is "thirty-one billion, three hundred twenty-one million, eleven thousand, twenty-one".