20611064640 has 112 divisors (see below), whose sum is σ = 66228821568. Its totient is φ = 5430042624.

The previous prime is 20611064629. The next prime is 20611064641. The reversal of 20611064640 is 4646011602.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 20611064598 and 20611064607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20611064641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49657 + ... + 209016.

It is an arithmetic number, because the mean of its divisors is an integer number (591328764).

Almost surely, 2^20611064640 is an apocalyptic number.

20611064640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20611064640 is an abundant number, since it is smaller than the sum of its proper divisors (45617756928).

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

20611064640 is a wasteful number, since it uses less digits than its factorization.

20611064640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258776 (or 258766 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The spelling of 20611064640 in words is "twenty billion, six hundred eleven million, sixty-four thousand, six hundred forty".