206781264 has 60 divisors (see below), whose sum is σ = 580305492. Its totient is φ = 68736000.

The previous prime is 206781257. The next prime is 206781287. The reversal of 206781264 is 462187602.

It can be written as a sum of positive squares in 2 ways, for example, as 197121600 + 9659664 = 14040^2 + 3108^2 .

It is a super-2 number, since 2×206781264² = 85516982282875392, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 55954 + ... + 59534.

Almost surely, 2^206781264 is an apocalyptic number.

206781264 is a gapful number since it is divisible by the number (24) 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 206781264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (290152746).

206781264 is an abundant number, since it is smaller than the sum of its proper divisors (373524228).

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

206781264 is a wasteful number, since it uses less digits than its factorization.

206781264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3996 (or 3987 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 206781264 is about 14379.8909592528. The cubic root of 206781264 is about 591.3397344088.

The spelling of 206781264 in words is "two hundred six million, seven hundred eighty-one thousand, two hundred sixty-four".