231211211021381 has 2 divisors, whose sum is σ = 231211211021382. Its totient is φ = 231211211021380.

The previous prime is 231211211021317. The next prime is 231211211021387. The reversal of 231211211021381 is 183120112112132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 147425857029025 + 83785353992356 = 12141905^2 + 9153434^2 .

It is a cyclic number.

It is not a de Polignac number, because 231211211021381 - 2⁶ = 231211211021317 is a prime.

It is a super-2 number, since 2×231211211021381² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231211211021387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115605605510690 + 115605605510691.

It is an arithmetic number, because the mean of its divisors is an integer number (115605605510691).

Almost surely, 2^{231211211021381} is an apocalyptic number.

It is an amenable number.

231211211021381 is a deficient number, since it is larger than the sum of its proper divisors (1).

231211211021381 is an equidigital number, since it uses as much as digits as its factorization.

231211211021381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 29.

The spelling of 231211211021381 in words is "two hundred thirty-one trillion, two hundred eleven billion, two hundred eleven million, twenty-one thousand, three hundred eighty-one".