1020205421 has 8 divisors (see below), whose sum is σ = 1030957824. Its totient is φ = 1009469520.

The previous prime is 1020205397. The next prime is 1020205423. The reversal of 1020205421 is 1245020201.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1020205421 - 2¹⁰ = 1020204397 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1020205421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020205423) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 149831 + ... + 156491.

It is an arithmetic number, because the mean of its divisors is an integer number (128869728).

Almost surely, 2^1020205421 is an apocalyptic number.

It is an amenable number.

1020205421 is a deficient number, since it is larger than the sum of its proper divisors (10752403).

1020205421 is a wasteful number, since it uses less digits than its factorization.

1020205421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8251.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 1020205421 is about 31940.6546739418. The cubic root of 1020205421 is about 1006.6902806594.

Adding to 1020205421 its reverse (1245020201), we get a palindrome (2265225622).

The spelling of 1020205421 in words is "one billion, twenty million, two hundred five thousand, four hundred twenty-one".