211513531 has 2 divisors, whose sum is σ = 211513532. Its totient is φ = 211513530.

The previous prime is 211513429. The next prime is 211513537. The reversal of 211513531 is 135315112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 211513531 - 2²¹ = 209416379 is a prime.

It is a super-2 number, since 2×211513531² = 89475947592175922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (211513537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105756765 + 105756766.

It is an arithmetic number, because the mean of its divisors is an integer number (105756766).

Almost surely, 2^211513531 is an apocalyptic number.

211513531 is a deficient number, since it is larger than the sum of its proper divisors (1).

211513531 is an equidigital number, since it uses as much as digits as its factorization.

211513531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 450, while the sum is 22.

The square root of 211513531 is about 14543.5047701715. The cubic root of 211513531 is about 595.8167640471.

Adding to 211513531 its reverse (135315112), we get a palindrome (346828643).

The spelling of 211513531 in words is "two hundred eleven million, five hundred thirteen thousand, five hundred thirty-one".