210781042 has 4 divisors (see below), whose sum is σ = 316171566. Its totient is φ = 105390520.

The previous prime is 210781033. The next prime is 210781069. The reversal of 210781042 is 240187012.

It is a happy number.

210781042 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 111957561 + 98823481 = 10581^2 + 9941^2 .

It is a junction number, because it is equal to n+sod(n) for n = 210780998 and 210781016.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 52695259 + ... + 52695262.

Almost surely, 2^210781042 is an apocalyptic number.

210781042 is a deficient number, since it is larger than the sum of its proper divisors (105390524).

210781042 is a wasteful number, since it uses less digits than its factorization.

210781042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105390523.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 210781042 is about 14518.3002448634. The cubic root of 210781042 is about 595.1281808439.

The spelling of 210781042 in words is "two hundred ten million, seven hundred eighty-one thousand, forty-two".