3121211381 has 8 divisors (see below), whose sum is σ = 3149512704. Its totient is φ = 3093037920.

The previous prime is 3121211363. The next prime is 3121211473. The reversal of 3121211381 is 1831121213.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3121211381 - 2²² = 3117017077 is a prime.

It is a super-2 number, since 2×3121211381² = 19483920969767854322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3121211341) 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 7 ways as a sum of consecutive naturals, for example, 17420 + ... + 80906.

It is an arithmetic number, because the mean of its divisors is an integer number (393689088).

Almost surely, 2^3121211381 is an apocalyptic number.

It is an amenable number.

3121211381 is a deficient number, since it is larger than the sum of its proper divisors (28301323).

3121211381 is a wasteful number, since it uses less digits than its factorization.

3121211381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63931.

The product of its digits is 288, while the sum is 23.

The square root of 3121211381 is about 55867.8027221404. The cubic root of 3121211381 is about 1461.4178040927.

Adding to 3121211381 its reverse (1831121213), we get a palindrome (4952332594).

The spelling of 3121211381 in words is "three billion, one hundred twenty-one million, two hundred eleven thousand, three hundred eighty-one".