856492381 has 2 divisors, whose sum is σ = 856492382. Its totient is φ = 856492380.

The previous prime is 856492367. The next prime is 856492387. The reversal of 856492381 is 183294658.

856492381 = T₂₃₈₉₄ + T₂₃₈₉₅ + T₂₃₈₉₆.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 837176356 + 19316025 = 28934^2 + 4395^2 .

It is a cyclic number.

It is not a de Polignac number, because 856492381 - 2⁷ = 856492253 is a prime.

It is a super-2 number, since 2×856492381² = 1467158397422098322, which contains 22 as substring.

It is equal to p_43897537 and since 856492381 and 43897537 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (856492387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428246190 + 428246191.

It is an arithmetic number, because the mean of its divisors is an integer number (428246191).

Almost surely, 2^856492381 is an apocalyptic number.

856492381 is the 23896-th centered triangular number.

It is an amenable number.

856492381 is a deficient number, since it is larger than the sum of its proper divisors (1).

856492381 is an equidigital number, since it uses as much as digits as its factorization.

856492381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 414720, while the sum is 46.

The square root of 856492381 is about 29265.8910850157. The cubic root of 856492381 is about 949.6738976761.

The spelling of 856492381 in words is "eight hundred fifty-six million, four hundred ninety-two thousand, three hundred eighty-one".