20021177660 has 24 divisors (see below), whose sum is σ = 45866698416. Its totient is φ = 7280428160.

The previous prime is 20021177653. The next prime is 20021177663. The reversal of 20021177660 is 6677112002.

It is a super-3 number, since 3×20021177660³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021177663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45502457 + ... + 45502896.

It is an arithmetic number, because the mean of its divisors is an integer number (1911112434).

Almost surely, 2^20021177660 is an apocalyptic number.

20021177660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20021177660 is an abundant number, since it is smaller than the sum of its proper divisors (25845520756).

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

20021177660 is a wasteful number, since it uses less digits than its factorization.

20021177660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91005373 (or 91005371 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 32.

Adding to 20021177660 its reverse (6677112002), we get a palindrome (26698289662).

The spelling of 20021177660 in words is "twenty billion, twenty-one million, one hundred seventy-seven thousand, six hundred sixty".