20640246464420 has 96 divisors (see below), whose sum is σ = 47331481317120. Its totient is φ = 7498158312960.

The previous prime is 20640246464353. The next prime is 20640246464459. The reversal of 20640246464420 is 2446464204602.

It is a super-4 number, since 4×20640246464420⁴ (a number of 54 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (44).

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, 1226460566 + ... + 1226477394.

It is an arithmetic number, because the mean of its divisors is an integer number (493036263720).

Almost surely, 2^{20640246464420} is an apocalyptic number.

20640246464420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20640246464420 is an abundant number, since it is smaller than the sum of its proper divisors (26691234852700).

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

20640246464420 is a wasteful number, since it uses less digits than its factorization.

20640246464420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22005 (or 22003 counting only the distinct ones).

The product of its (nonzero) digits is 1769472, while the sum is 44.

The spelling of 20640246464420 in words is "twenty trillion, six hundred forty billion, two hundred forty-six million, four hundred sixty-four thousand, four hundred twenty".