221021013431 has 2 divisors, whose sum is σ = 221021013432. Its totient is φ = 221021013430.

The previous prime is 221021013407. The next prime is 221021013469. The reversal of 221021013431 is 134310120122.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221021013431 is a prime.

It is a super-2 number, since 2×221021013431² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221021073431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110510506715 + 110510506716.

It is an arithmetic number, because the mean of its divisors is an integer number (110510506716).

Almost surely, 2^221021013431 is an apocalyptic number.

221021013431 is a deficient number, since it is larger than the sum of its proper divisors (1).

221021013431 is an equidigital number, since it uses as much as digits as its factorization.

221021013431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 221021013431 its reverse (134310120122), we get a palindrome (355331133553).

The spelling of 221021013431 in words is "two hundred twenty-one billion, twenty-one million, thirteen thousand, four hundred thirty-one".