1653661220 has 12 divisors (see below), whose sum is σ = 3472688604. Its totient is φ = 661464480.

The previous prime is 1653661211. The next prime is 1653661279. The reversal of 1653661220 is 221663561.

1653661220 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 1123188196 + 530473024 = 33514^2 + 23032^2 .

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 3 ways as a sum of consecutive naturals, for example, 41341511 + ... + 41341550.

It is an arithmetic number, because the mean of its divisors is an integer number (289390717).

Almost surely, 2^1653661220 is an apocalyptic number.

1653661220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1653661220 is an abundant number, since it is smaller than the sum of its proper divisors (1819027384).

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

1653661220 is a wasteful number, since it uses less digits than its factorization.

1653661220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82683070 (or 82683068 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 1653661220 is about 40665.2335539832. The cubic root of 1653661220 is about 1182.5391125449.

The spelling of 1653661220 in words is "one billion, six hundred fifty-three million, six hundred sixty-one thousand, two hundred twenty".