20420623397544 has 64 divisors (see below), whose sum is σ = 54091091658240. Its totient is φ = 6402144122880.

The previous prime is 20420623397509. The next prime is 20420623397567. The reversal of 20420623397544 is 44579332602402.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16293304 + ... + 17501799.

It is an arithmetic number, because the mean of its divisors is an integer number (845173307160).

Almost surely, 2^{20420623397544} is an apocalyptic number.

20420623397544 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20420623397544 is an abundant number, since it is smaller than the sum of its proper divisors (33670468260696).

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

20420623397544 is a wasteful number, since it uses less digits than its factorization.

20420623397544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33796610 (or 33796606 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 51.

Adding to 20420623397544 its reverse (44579332602402), we get a palindrome (64999955999946).

The spelling of 20420623397544 in words is "twenty trillion, four hundred twenty billion, six hundred twenty-three million, three hundred ninety-seven thousand, five hundred forty-four".