20177980 has 36 divisors (see below), whose sum is σ = 45025848. Its totient is φ = 7594240.

The previous prime is 20177977. The next prime is 20177999. The reversal of 20177980 is 8977102.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 4035 + ... + 7525.

It is an arithmetic number, because the mean of its divisors is an integer number (1250718).

Almost surely, 2^20177980 is an apocalyptic number.

20177980 is a gapful number since it is divisible by the number (20) 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 20177980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22512924).

20177980 is an abundant number, since it is smaller than the sum of its proper divisors (24847868).

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

20177980 is a wasteful number, since it uses less digits than its factorization.

20177980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3534 (or 3515 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 34.

The square root of 20177980 is about 4491.9906500348. The cubic root of 20177980 is about 272.2445716915.

The spelling of 20177980 in words is "twenty million, one hundred seventy-seven thousand, nine hundred eighty".