1621722325 has 12 divisors (see below), whose sum is σ = 2028735108. Its totient is φ = 1285894400.

The previous prime is 1621722299. The next prime is 1621722329. The reversal of 1621722325 is 5232271261.

It can be written as a sum of positive squares in 6 ways, for example, as 302725201 + 1318997124 = 17399^2 + 36318^2 .

It is not a de Polignac number, because 1621722325 - 2¹⁵ = 1621689557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1621722329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 284206 + ... + 289855.

It is an arithmetic number, because the mean of its divisors is an integer number (169061259).

Almost surely, 2^1621722325 is an apocalyptic number.

It is an amenable number.

1621722325 is a deficient number, since it is larger than the sum of its proper divisors (407012783).

1621722325 is a wasteful number, since it uses less digits than its factorization.

1621722325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 574184 (or 574179 counting only the distinct ones).

The product of its digits is 10080, while the sum is 31.

The square root of 1621722325 is about 40270.6136655502. The cubic root of 1621722325 is about 1174.8763594061.

Adding to 1621722325 its reverse (5232271261), we get a palindrome (6853993586).

The spelling of 1621722325 in words is "one billion, six hundred twenty-one million, seven hundred twenty-two thousand, three hundred twenty-five".