1661727064 has 32 divisors (see below), whose sum is σ = 3159641520. Its totient is φ = 819197056.

The previous prime is 1661727031. The next prime is 1661727071. The reversal of 1661727064 is 4607271661.

It is a super-2 number, since 2×1661727064² = 5522673670460120192, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 367602 + ... + 372094.

Almost surely, 2^1661727064 is an apocalyptic number.

It is an amenable number.

1661727064 is a deficient number, since it is larger than the sum of its proper divisors (1497914456).

1661727064 is a wasteful number, since it uses less digits than its factorization.

1661727064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5139 (or 5135 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 40.

The square root of 1661727064 is about 40764.2866244462. The cubic root of 1661727064 is about 1184.4586331170.

It can be divided in two parts, 16617 and 27064, that added together give a square (43681 = 209²).

The spelling of 1661727064 in words is "one billion, six hundred sixty-one million, seven hundred twenty-seven thousand, sixty-four".