1620520064 has 32 divisors (see below), whose sum is σ = 3247085340. Its totient is φ = 805565440.

The previous prime is 1620520063. The next prime is 1620520129. The reversal of 1620520064 is 4600250261.

It can be written as a sum of positive squares in 2 ways, for example, as 1599360064 + 21160000 = 39992^2 + 4600^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is not an unprimeable number, because it can be changed into a prime (1620520063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14447 + ... + 58734.

Almost surely, 2^1620520064 is an apocalyptic number.

It is an amenable number.

1620520064 is an abundant number, since it is smaller than the sum of its proper divisors (1626565276).

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

1620520064 is an equidigital number, since it uses as much as digits as its factorization.

1620520064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73368 (or 73356 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 1620520064 is about 40255.6836235581. The cubic root of 1620520064 is about 1174.5859567886.

The spelling of 1620520064 in words is "one billion, six hundred twenty million, five hundred twenty thousand, sixty-four".