1022720401 has 4 divisors (see below), whose sum is σ = 1023360804. Its totient is φ = 1022080000.

The previous prime is 1022720393. The next prime is 1022720417. The reversal of 1022720401 is 1040272201.

It is a happy number.

It is a Cunningham number, because it is equal to 31980²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1020163600 + 2556801 = 31940^2 + 1599^2 .

It is a cyclic number.

It is not a de Polignac number, because 1022720401 - 2³ = 1022720393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1022720431) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 317800 + ... + 321001.

It is an arithmetic number, because the mean of its divisors is an integer number (255840201).

Almost surely, 2^1022720401 is an apocalyptic number.

It is an amenable number.

1022720401 is a deficient number, since it is larger than the sum of its proper divisors (640403).

1022720401 is an equidigital number, since it uses as much as digits as its factorization.

1022720401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 640402.

The product of its (nonzero) digits is 224, while the sum is 19.

The square root of 1022720401 is about 31980.0000156348. Note that the first 4 decimals coincide. The cubic root of 1022720401 is about 1007.5168228016.

Adding to 1022720401 its reverse (1040272201), we get a palindrome (2062992602).

It can be divided in two parts, 10227 and 20401, that added together give a triangular number (30628 = T₂₄₇).

The spelling of 1022720401 in words is "one billion, twenty-two million, seven hundred twenty thousand, four hundred one".