431221020 has 96 divisors (see below), whose sum is σ = 1274434560. Its totient is φ = 108725760.

The previous prime is 431221013. The next prime is 431221027. The reversal of 431221020 is 20122134.

It is an interprime number because it is at equal distance from previous prime (431221013) and next prime (431221027).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (431221027) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 121065 + ... + 124575.

It is an arithmetic number, because the mean of its divisors is an integer number (13275360).

Almost surely, 2^431221020 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 431221020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (637217280).

431221020 is an abundant number, since it is smaller than the sum of its proper divisors (843213540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

431221020 is a wasteful number, since it uses less digits than its factorization.

431221020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3635 (or 3633 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 431221020 is about 20765.8618891680. The cubic root of 431221020 is about 755.4979800257.

Adding to 431221020 its reverse (20122134), we get a palindrome (451343154).

The spelling of 431221020 in words is "four hundred thirty-one million, two hundred twenty-one thousand, twenty".