162251531021 has 2 divisors, whose sum is σ = 162251531022. Its totient is φ = 162251531020.

The previous prime is 162251530979. The next prime is 162251531023. The reversal of 162251531021 is 120135152261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 138469573225 + 23781957796 = 372115^2 + 154214^2 .

It is a cyclic number.

It is not a de Polignac number, because 162251531021 - 2¹⁰ = 162251529997 is a prime.

Together with 162251531023, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (162251531023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81125765510 + 81125765511.

It is an arithmetic number, because the mean of its divisors is an integer number (81125765511).

Almost surely, 2^162251531021 is an apocalyptic number.

It is an amenable number.

162251531021 is a deficient number, since it is larger than the sum of its proper divisors (1).

162251531021 is an equidigital number, since it uses as much as digits as its factorization.

162251531021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3600, while the sum is 29.

Adding to 162251531021 its reverse (120135152261), we get a palindrome (282386683282).

The spelling of 162251531021 in words is "one hundred sixty-two billion, two hundred fifty-one million, five hundred thirty-one thousand, twenty-one".