855211531 has 2 divisors, whose sum is σ = 855211532. Its totient is φ = 855211530.

The previous prime is 855211501. The next prime is 855211547. The reversal of 855211531 is 135112558.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 855211531 - 2¹⁵ = 855178763 is a prime.

It is a super-2 number, since 2×855211531² = 1462773525510727922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 855211493 and 855211502.

It is not a weakly prime, because it can be changed into another prime (855211501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 427605765 + 427605766.

It is an arithmetic number, because the mean of its divisors is an integer number (427605766).

Almost surely, 2^855211531 is an apocalyptic number.

855211531 is a deficient number, since it is larger than the sum of its proper divisors (1).

855211531 is an equidigital number, since it uses as much as digits as its factorization.

855211531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6000, while the sum is 31.

The square root of 855211531 is about 29243.9999145124. Note that the first 4 decimals coincide. The cubic root of 855211531 is about 949.2002617562.

The spelling of 855211531 in words is "eight hundred fifty-five million, two hundred eleven thousand, five hundred thirty-one".