20001215542 has 48 divisors (see below), whose sum is σ = 38204754336. Its totient is φ = 7685884800.

The previous prime is 20001215539. The next prime is 20001215567. The reversal of 20001215542 is 24551210002.

It is a super-3 number, since 3×20001215542³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 42792 + ... + 204532.

It is an arithmetic number, because the mean of its divisors is an integer number (795932382).

Almost surely, 2^20001215542 is an apocalyptic number.

20001215542 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

20001215542 is a deficient number, since it is larger than the sum of its proper divisors (18203538794).

20001215542 is a wasteful number, since it uses less digits than its factorization.

20001215542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161845 (or 161834 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

Adding to 20001215542 its reverse (24551210002), we get a palindrome (44552425544).

The spelling of 20001215542 in words is "twenty billion, one million, two hundred fifteen thousand, five hundred forty-two".