1021650660 has 144 divisors (see below), whose sum is σ = 3209798592. Its totient is φ = 262828800.

The previous prime is 1021650613. The next prime is 1021650709. The reversal of 1021650660 is 660561201.

It is a happy number.

1021650660 is a `hidden beast` number, since 1 + 0 + 2 + 1 + 650 + 6 + 6 + 0 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 871875 + ... + 873045.

It is an arithmetic number, because the mean of its divisors is an integer number (22290268).

Almost surely, 2^1021650660 is an apocalyptic number.

1021650660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1021650660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1604899296).

1021650660 is an abundant number, since it is smaller than the sum of its proper divisors (2188147932).

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

1021650660 is a wasteful number, since it uses less digits than its factorization.

1021650660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1354 (or 1349 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 1021650660 is about 31963.2704834784. The cubic root of 1021650660 is about 1007.1654207797.

The spelling of 1021650660 in words is "one billion, twenty-one million, six hundred fifty thousand, six hundred sixty".