1667581020 has 240 divisors, whose sum is σ = 6010583040. Its totient is φ = 379126656.

The previous prime is 1667581001. The next prime is 1667581057. The reversal of 1667581020 is 201857661.

1667581020 is a `hidden beast` number, since 16 + 67 + 581 + 0 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3481141 + ... + 3481619.

It is an arithmetic number, because the mean of its divisors is an integer number (25044096).

Almost surely, 2^1667581020 is an apocalyptic number.

1667581020 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 1667581020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3005291520).

1667581020 is an abundant number, since it is smaller than the sum of its proper divisors (4343002020).

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

1667581020 is a wasteful number, since it uses less digits than its factorization.

1667581020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 814 (or 803 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 1667581020 is about 40836.0260064566. The cubic root of 1667581020 is about 1185.8478790092.

The spelling of 1667581020 in words is "one billion, six hundred sixty-seven million, five hundred eighty-one thousand, twenty".