210256642 has 4 divisors (see below), whose sum is σ = 315384966. Its totient is φ = 105128320.

The previous prime is 210256621. The next prime is 210256643. The reversal of 210256642 is 246652012.

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., 130850721 + 79405921 = 11439^2 + 8911^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 210256642.

It is not an unprimeable number, because it can be changed into a prime (210256643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52564159 + ... + 52564162.

Almost surely, 2^210256642 is an apocalyptic number.

210256642 is a deficient number, since it is larger than the sum of its proper divisors (105128324).

210256642 is a wasteful number, since it uses less digits than its factorization.

210256642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105128323.

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 210256642 is about 14500.2290326739. The cubic root of 210256642 is about 594.6342332153.

The spelling of 210256642 in words is "two hundred ten million, two hundred fifty-six thousand, six hundred forty-two".