2156246381 has 2 divisors, whose sum is σ = 2156246382. Its totient is φ = 2156246380.

The previous prime is 2156246371. The next prime is 2156246413. The reversal of 2156246381 is 1836426512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1380122500 + 776123881 = 37150^2 + 27859^2 .

It is a cyclic number.

It is not a de Polignac number, because 2156246381 - 2⁶ = 2156246317 is a prime.

It is a super-2 number, since 2×2156246381² = 9298796911151194322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2156246371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1078123190 + 1078123191.

It is an arithmetic number, because the mean of its divisors is an integer number (1078123191).

Almost surely, 2^2156246381 is an apocalyptic number.

It is an amenable number.

2156246381 is a deficient number, since it is larger than the sum of its proper divisors (1).

2156246381 is an equidigital number, since it uses as much as digits as its factorization.

2156246381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 69120, while the sum is 38.

The square root of 2156246381 is about 46435.4000844184. The cubic root of 2156246381 is about 1291.9115903186.

The spelling of 2156246381 in words is "two billion, one hundred fifty-six million, two hundred forty-six thousand, three hundred eighty-one".