21155100421003 has 8 divisors (see below), whose sum is σ = 21210837631488. Its totient is φ = 21099365825664.

The previous prime is 21155100420967. The next prime is 21155100421027. The reversal of 21155100421003 is 30012400155112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21155100421003 - 2¹³ = 21155100412811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21155100121003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16111875 + ... + 17375347.

It is an arithmetic number, because the mean of its divisors is an integer number (2651354703936).

Almost surely, 2^{21155100421003} is an apocalyptic number.

21155100421003 is a deficient number, since it is larger than the sum of its proper divisors (55737210485).

21155100421003 is a wasteful number, since it uses less digits than its factorization.

21155100421003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1307573.

The product of its (nonzero) digits is 1200, while the sum is 25.

Adding to 21155100421003 its reverse (30012400155112), we get a palindrome (51167500576115).

The spelling of 21155100421003 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred million, four hundred twenty-one thousand, three".