167772421 has 2 divisors, whose sum is σ = 167772422. Its totient is φ = 167772420.

The previous prime is 167772389. The next prime is 167772431. The reversal of 167772421 is 124277761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139830625 + 27941796 = 11825^2 + 5286^2 .

It is a cyclic number.

It is not a de Polignac number, because 167772421 - 2⁵ = 167772389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (167772431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83886210 + 83886211.

It is an arithmetic number, because the mean of its divisors is an integer number (83886211).

Almost surely, 2^167772421 is an apocalyptic number.

It is an amenable number.

167772421 is a deficient number, since it is larger than the sum of its proper divisors (1).

167772421 is an equidigital number, since it uses as much as digits as its factorization.

167772421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32928, while the sum is 37.

The square root of 167772421 is about 12952.6993711736. The cubic root of 167772421 is about 551.5355666524.

The spelling of 167772421 in words is "one hundred sixty-seven million, seven hundred seventy-two thousand, four hundred twenty-one".