210149640 has 160 divisors (see below), whose sum is σ = 725840280. Its totient is φ = 54494208.

The previous prime is 210149623. The next prime is 210149647. The reversal of 210149640 is 46941012.

210149640 is a `hidden beast` number, since 2 + 1 + 0 + 14 + 9 + 640 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 153809604 + 56340036 = 12402^2 + 7506^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210149647) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 119004 + ... + 120756.

Almost surely, 2^210149640 is an apocalyptic number.

210149640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 210149640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (362920140).

210149640 is an abundant number, since it is smaller than the sum of its proper divisors (515690640).

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

210149640 is a wasteful number, since it uses less digits than its factorization.

210149640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1813 (or 1800 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 210149640 is about 14496.5388972679. The cubic root of 210149640 is about 594.5333440540.

The spelling of 210149640 in words is "two hundred ten million, one hundred forty-nine thousand, six hundred forty".