21501264377138 has 32 divisors (see below), whose sum is σ = 40367432488320. Its totient is φ = 8361825292800.

The previous prime is 21501264377101. The next prime is 21501264377171. The reversal of 21501264377138 is 83177346210512.

It is a super-3 number, since 3×21501264377138³ (a number of 41 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1001165663 + ... + 1001187138.

It is an arithmetic number, because the mean of its divisors is an integer number (1261482265260).

Almost surely, 2^{21501264377138} is an apocalyptic number.

21501264377138 is a deficient number, since it is larger than the sum of its proper divisors (18866168111182).

21501264377138 is a wasteful number, since it uses less digits than its factorization.

21501264377138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2002352882.

The product of its (nonzero) digits is 1693440, while the sum is 50.

The spelling of 21501264377138 in words is "twenty-one trillion, five hundred one billion, two hundred sixty-four million, three hundred seventy-seven thousand, one hundred thirty-eight".