84131381 has 2 divisors, whose sum is σ = 84131382. Its totient is φ = 84131380.

The previous prime is 84131371. The next prime is 84131389. The reversal of 84131381 is 18313148.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46799281 + 37332100 = 6841^2 + 6110^2 .

It is a cyclic number.

It is not a de Polignac number, because 84131381 - 2¹⁰ = 84130357 is a prime.

It is a super-2 number, since 2×84131381² = 14156178537934322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84131389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42065690 + 42065691.

It is an arithmetic number, because the mean of its divisors is an integer number (42065691).

Almost surely, 2^84131381 is an apocalyptic number.

It is an amenable number.

84131381 is a deficient number, since it is larger than the sum of its proper divisors (1).

84131381 is an equidigital number, since it uses as much as digits as its factorization.

84131381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2304, while the sum is 29.

The square root of 84131381 is about 9172.3160106922. The cubic root of 84131381 is about 438.1801226735.

The spelling of 84131381 in words is "eighty-four million, one hundred thirty-one thousand, three hundred eighty-one".