1660967820 has 72 divisors (see below), whose sum is σ = 5044799760. Its totient is φ = 442350720.

The previous prime is 1660967807. The next prime is 1660967831. The reversal of 1660967820 is 287690661.

1660967820 is a `hidden beast` number, since 16 + 609 + 6 + 7 + 8 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 143655 + ... + 154785.

Almost surely, 2^1660967820 is an apocalyptic number.

1660967820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1660967820 is an abundant number, since it is smaller than the sum of its proper divisors (3383831940).

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

1660967820 is a wasteful number, since it uses less digits than its factorization.

1660967820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11975 (or 11970 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 1660967820 is about 40754.9729480955. The cubic root of 1660967820 is about 1184.2782123713.

The spelling of 1660967820 in words is "one billion, six hundred sixty million, nine hundred sixty-seven thousand, eight hundred twenty".