212123151531 has 24 divisors (see below), whose sum is σ = 327400032960. Its totient is φ = 131875796736.

The previous prime is 212123151509. The next prime is 212123151547. The reversal of 212123151531 is 135151321212.

212123151531 is a `hidden beast` number, since 2 + 1 + 2 + 123 + 1 + 5 + 1 + 531 = 666.

212123151531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 212123151531 - 2⁷ = 212123151403 is a prime.

It is a super-2 number, since 2×212123151531² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 212123151495 and 212123151504.

It is not an unprimeable number, because it can be changed into a prime (212123151551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6343075 + ... + 6376428.

It is an arithmetic number, because the mean of its divisors is an integer number (13641668040).

Almost surely, 2^212123151531 is an apocalyptic number.

212123151531 is a deficient number, since it is larger than the sum of its proper divisors (115276881429).

212123151531 is a wasteful number, since it uses less digits than its factorization.

212123151531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12719635 (or 12719632 counting only the distinct ones).

The product of its digits is 1800, while the sum is 27.

Adding to 212123151531 its reverse (135151321212), we get a palindrome (347274472743).

The spelling of 212123151531 in words is "two hundred twelve billion, one hundred twenty-three million, one hundred fifty-one thousand, five hundred thirty-one".