21504040400151 has 12 divisors (see below), whose sum is σ = 31219063730712. Its totient is φ = 14263255221936.

The previous prime is 21504040400149. The next prime is 21504040400173. The reversal of 21504040400151 is 15100404040512.

21504040400151 is a `hidden beast` number, since 2 + 1 + 504 + 0 + 4 + 0 + 4 + 0 + 0 + 151 = 666.

It is not a de Polignac number, because 21504040400151 - 2¹ = 21504040400149 is a prime.

It is a super-3 number, since 3×21504040400151³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21504040400111) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 6064307421 + ... + 6064310966.

It is an arithmetic number, because the mean of its divisors is an integer number (2601588644226).

Almost surely, 2^{21504040400151} is an apocalyptic number.

21504040400151 is a deficient number, since it is larger than the sum of its proper divisors (9715023330561).

21504040400151 is a wasteful number, since it uses less digits than its factorization.

21504040400151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12128618590 (or 12128618587 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

Adding to 21504040400151 its reverse (15100404040512), we get a palindrome (36604444440663).

The spelling of 21504040400151 in words is "twenty-one trillion, five hundred four billion, forty million, four hundred thousand, one hundred fifty-one".