212640642 has 24 divisors (see below), whose sum is σ = 461314620. Its totient is φ = 70788960.

The previous prime is 212640601. The next prime is 212640677. The reversal of 212640642 is 246046212.

212640642 is a `hidden beast` number, since 2 + 12 + 6 + 4 + 0 + 642 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 201611601 + 11029041 = 14199^2 + 3321^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7584 + ... + 21972.

Almost surely, 2^212640642 is an apocalyptic number.

212640642 is an abundant number, since it is smaller than the sum of its proper divisors (248673978).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212640642 is a wasteful number, since it uses less digits than its factorization.

212640642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15218 (or 15215 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 212640642 is about 14582.2029199981. The cubic root of 212640642 is about 596.8732170191.

Adding to 212640642 its reverse (246046212), we get a palindrome (458686854).

The spelling of 212640642 in words is "two hundred twelve million, six hundred forty thousand, six hundred forty-two".