2064401661 has 16 divisors (see below), whose sum is σ = 3311321600. Its totient is φ = 1117570608.

The previous prime is 2064401657. The next prime is 2064401723. The reversal of 2064401661 is 1661044602.

It is not a de Polignac number, because 2064401661 - 2² = 2064401657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2064401641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2586571 + ... + 2587368.

It is an arithmetic number, because the mean of its divisors is an integer number (206957600).

Almost surely, 2^2064401661 is an apocalyptic number.

2064401661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2064401661 is a deficient number, since it is larger than the sum of its proper divisors (1246919939).

2064401661 is a wasteful number, since it uses less digits than its factorization.

2064401661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5173968.

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 2064401661 is about 45435.6870862541. The cubic root of 2064401661 is about 1273.3019375789.

The spelling of 2064401661 in words is "two billion, sixty-four million, four hundred one thousand, six hundred sixty-one".