3121403381 has 2 divisors, whose sum is σ = 3121403382. Its totient is φ = 3121403380.

The previous prime is 3121403377. The next prime is 3121403471. The reversal of 3121403381 is 1833041213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2007846481 + 1113556900 = 44809^2 + 33370^2 .

It is a cyclic number.

It is not a de Polignac number, because 3121403381 - 2² = 3121403377 is a prime.

It is a super-2 number, since 2×3121403381² = 19486318133836462322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 3121403381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3121405381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1560701690 + 1560701691.

It is an arithmetic number, because the mean of its divisors is an integer number (1560701691).

Almost surely, 2^3121403381 is an apocalyptic number.

It is an amenable number.

3121403381 is a deficient number, since it is larger than the sum of its proper divisors (1).

3121403381 is an equidigital number, since it uses as much as digits as its factorization.

3121403381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 3121403381 is about 55869.5210378611. The cubic root of 3121403381 is about 1461.4477696446.

Adding to 3121403381 its reverse (1833041213), we get a palindrome (4954444594).

The spelling of 3121403381 in words is "three billion, one hundred twenty-one million, four hundred three thousand, three hundred eighty-one".