21030223031 has 16 divisors (see below), whose sum is σ = 22805161344. Its totient is φ = 19320643584.

The previous prime is 21030223003. The next prime is 21030223037. The reversal of 21030223031 is 13032203012.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21030223031 is a prime.

It is a super-2 number, since 2×21030223031² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21030223037) 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, 33026 + ... + 207728.

It is an arithmetic number, because the mean of its divisors is an integer number (1425322584).

Almost surely, 2^21030223031 is an apocalyptic number.

21030223031 is a deficient number, since it is larger than the sum of its proper divisors (1774938313).

21030223031 is a wasteful number, since it uses less digits than its factorization.

21030223031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174890.

The product of its (nonzero) digits is 216, while the sum is 17.

Adding to 21030223031 its reverse (13032203012), we get a palindrome (34062426043).

The spelling of 21030223031 in words is "twenty-one billion, thirty million, two hundred twenty-three thousand, thirty-one".