1667651220 has 96 divisors (see below), whose sum is σ = 5314861440. Its totient is φ = 433854720.

The previous prime is 1667651213. The next prime is 1667651233. The reversal of 1667651220 is 221567661.

It is a happy number.

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 31 ways as a sum of consecutive naturals, for example, 15522 + ... + 59801.

It is an arithmetic number, because the mean of its divisors is an integer number (55363140).

Almost surely, 2^1667651220 is an apocalyptic number.

1667651220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1667651220 is an abundant number, since it is smaller than the sum of its proper divisors (3647210220).

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

1667651220 is a wasteful number, since it uses less digits than its factorization.

1667651220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75382 (or 75374 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 1667651220 is about 40836.8855325672. The cubic root of 1667651220 is about 1185.8645189509.

It can be divided in two parts, 16676 and 51220, that added together give a triangular number (67896 = T₃₆₈).

The spelling of 1667651220 in words is "one billion, six hundred sixty-seven million, six hundred fifty-one thousand, two hundred twenty".