212403731 has 4 divisors (see below), whose sum is σ = 212973552. Its totient is φ = 211833912.

The previous prime is 212403721. The next prime is 212403733. The reversal of 212403731 is 137304212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 212403731 - 2¹⁴ = 212387347 is a prime.

It is a super-2 number, since 2×212403731² = 90230689885440722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212403697 and 212403706.

It is not an unprimeable number, because it can be changed into a prime (212403733) 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, 284351 + ... + 285096.

It is an arithmetic number, because the mean of its divisors is an integer number (53243388).

Almost surely, 2^212403731 is an apocalyptic number.

212403731 is a deficient number, since it is larger than the sum of its proper divisors (569821).

212403731 is an equidigital number, since it uses as much as digits as its factorization.

212403731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 569820.

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 212403731 is about 14574.0773635932. The cubic root of 212403731 is about 596.6514682867.

Adding to 212403731 its reverse (137304212), we get a palindrome (349707943).

The spelling of 212403731 in words is "two hundred twelve million, four hundred three thousand, seven hundred thirty-one".