1620646650 has 192 divisors, whose sum is σ = 5129314560. Its totient is φ = 368582400.

The previous prime is 1620646607. The next prime is 1620646661. The reversal of 1620646650 is 566460261.

It is a happy number.

1620646650 is a `hidden beast` number, since 1 + 6 + 2 + 0 + 646 + 6 + 5 + 0 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2995380 + ... + 2995920.

It is an arithmetic number, because the mean of its divisors is an integer number (26715180).

Almost surely, 2^1620646650 is an apocalyptic number.

1620646650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1620646650, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2564657280).

1620646650 is an abundant number, since it is smaller than the sum of its proper divisors (3508667910).

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

1620646650 is a wasteful number, since it uses less digits than its factorization.

1620646650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 886 (or 875 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 1620646650 is about 40257.2558677315. The cubic root of 1620646650 is about 1174.6165400296.

The spelling of 1620646650 in words is "one billion, six hundred twenty million, six hundred forty-six thousand, six hundred fifty".