21420420431033 has 16 divisors (see below), whose sum is σ = 23865818424000. Its totient is φ = 19089102634560.

The previous prime is 21420420431017. The next prime is 21420420431107. The reversal of 21420420431033 is 33013402402412.

It is a cyclic number.

It is not a de Polignac number, because 21420420431033 - 2⁴ = 21420420431017 is a prime.

It is a super-2 number, since 2×21420420431033² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a junction number, because it is equal to n+sod(n) for n = 21420420430987 and 21420420431005.

It is not an unprimeable number, because it can be changed into a prime (21420420491033) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1423118 + ... + 6698216.

It is an arithmetic number, because the mean of its divisors is an integer number (1491613651500).

Almost surely, 2^{21420420431033} is an apocalyptic number.

It is an amenable number.

21420420431033 is a deficient number, since it is larger than the sum of its proper divisors (2445397992967).

21420420431033 is a wasteful number, since it uses less digits than its factorization.

21420420431033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5285912.

The product of its (nonzero) digits is 13824, while the sum is 29.

Adding to 21420420431033 its reverse (33013402402412), we get a palindrome (54433822833445).

The spelling of 21420420431033 in words is "twenty-one trillion, four hundred twenty billion, four hundred twenty million, four hundred thirty-one thousand, thirty-three".