1641618720 has 144 divisors (see below), whose sum is σ = 6402352320. Its totient is φ = 375224832.

The previous prime is 1641618703. The next prime is 1641618731. The reversal of 1641618720 is 278161461.

It is a happy number.

1641618720 is a `hidden beast` number, since 1 + 641 + 6 + 1 + 8 + 7 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

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

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 23 ways as a sum of consecutive naturals, for example, 71350 + ... + 91509.

It is an arithmetic number, because the mean of its divisors is an integer number (44460780).

Almost surely, 2^1641618720 is an apocalyptic number.

1641618720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1641618720 is an abundant number, since it is smaller than the sum of its proper divisors (4760733600).

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

1641618720 is a wasteful number, since it uses less digits than its factorization.

1641618720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162887 (or 162876 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 1641618720 is about 40516.8942541256. The cubic root of 1641618720 is about 1179.6615710495.

The spelling of 1641618720 in words is "one billion, six hundred forty-one million, six hundred eighteen thousand, seven hundred twenty".