21121231433 has 2 divisors, whose sum is σ = 21121231434. Its totient is φ = 21121231432.

The previous prime is 21121231429. The next prime is 21121231451. The reversal of 21121231433 is 33413212112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11502133504 + 9619097929 = 107248^2 + 98077^2 .

It is a cyclic number.

It is not a de Polignac number, because 21121231433 - 2² = 21121231429 is a prime.

It is a super-2 number, since 2×21121231433² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121231399 and 21121231408.

It is not a weakly prime, because it can be changed into another prime (21121231493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560615716 + 10560615717.

It is an arithmetic number, because the mean of its divisors is an integer number (10560615717).

Almost surely, 2^21121231433 is an apocalyptic number.

It is an amenable number.

21121231433 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121231433 is an equidigital number, since it uses as much as digits as its factorization.

21121231433 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864, while the sum is 23.

Adding to 21121231433 its reverse (33413212112), we get a palindrome (54534443545).

The spelling of 21121231433 in words is "twenty-one billion, one hundred twenty-one million, two hundred thirty-one thousand, four hundred thirty-three".