1781628064 has 12 divisors (see below), whose sum is σ = 3507580314. Its totient is φ = 890814016.

The previous prime is 1781628061. The next prime is 1781628071. The reversal of 1781628064 is 4608261871.

It can be written as a sum of positive squares in only one way, i.e., 1559618064 + 222010000 = 39492^2 + 14900^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1781628064.

It is not an unprimeable number, because it can be changed into a prime (1781628061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27837907 + ... + 27837970.

Almost surely, 2^1781628064 is an apocalyptic number.

It is an amenable number.

1781628064 is a deficient number, since it is larger than the sum of its proper divisors (1725952250).

1781628064 is an equidigital number, since it uses as much as digits as its factorization.

1781628064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55675887 (or 55675879 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 43.

The square root of 1781628064 is about 42209.3362184245. The cubic root of 1781628064 is about 1212.2876522454.

The spelling of 1781628064 in words is "one billion, seven hundred eighty-one million, six hundred twenty-eight thousand, sixty-four".