21246153605431 has 16 divisors (see below), whose sum is σ = 21405676750848. Its totient is φ = 21087253720000.

The previous prime is 21246153605387. The next prime is 21246153605491. The reversal of 21246153605431 is 13450635164212.

It is a cyclic number.

It is not a de Polignac number, because 21246153605431 - 2⁴¹ = 19047130349879 is a prime.

It is a super-2 number, since 2×21246153605431² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21246153605491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 262806186 + ... + 262887016.

It is an arithmetic number, because the mean of its divisors is an integer number (1337854796928).

Almost surely, 2^{21246153605431} is an apocalyptic number.

21246153605431 is a deficient number, since it is larger than the sum of its proper divisors (159523145417).

21246153605431 is a wasteful number, since it uses less digits than its factorization.

21246153605431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84662.

The product of its (nonzero) digits is 518400, while the sum is 43.

Adding to 21246153605431 its reverse (13450635164212), we get a palindrome (34696788769643).

The spelling of 21246153605431 in words is "twenty-one trillion, two hundred forty-six billion, one hundred fifty-three million, six hundred five thousand, four hundred thirty-one".