213931428 has 12 divisors (see below), whose sum is σ = 499173360. Its totient is φ = 71310472.

The previous prime is 213931427. The next prime is 213931489. The reversal of 213931428 is 824139312.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×213931428² = 91533311772238368, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (213931427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8913798 + ... + 8913821.

It is an arithmetic number, because the mean of its divisors is an integer number (41597780).

Almost surely, 2^213931428 is an apocalyptic number.

It is an amenable number.

213931428 is an abundant number, since it is smaller than the sum of its proper divisors (285241932).

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

213931428 is a wasteful number, since it uses less digits than its factorization.

213931428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17827626 (or 17827624 counting only the distinct ones).

The product of its digits is 10368, while the sum is 33.

The square root of 213931428 is about 14626.3949078370. The cubic root of 213931428 is about 598.0785085756.

The spelling of 213931428 in words is "two hundred thirteen million, nine hundred thirty-one thousand, four hundred twenty-eight".