1021530623421 has 16 divisors (see below), whose sum is σ = 1698128828928. Its totient is φ = 530665258800.

The previous prime is 1021530623401. The next prime is 1021530623423. The reversal of 1021530623421 is 1243260351201.

It is not a de Polignac number, because 1021530623421 - 2¹⁸ = 1021530361277 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021530623423) 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, 2211105015 + ... + 2211105476.

It is an arithmetic number, because the mean of its divisors is an integer number (106133051808).

Almost surely, 2^{1021530623421} is an apocalyptic number.

1021530623421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1021530623421 is a deficient number, since it is larger than the sum of its proper divisors (676598205507).

1021530623421 is a wasteful number, since it uses less digits than its factorization.

1021530623421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4422210512.

The product of its (nonzero) digits is 8640, while the sum is 30.

Adding to 1021530623421 its reverse (1243260351201), we get a palindrome (2264790974622).

The spelling of 1021530623421 in words is "one trillion, twenty-one billion, five hundred thirty million, six hundred twenty-three thousand, four hundred twenty-one".