331551421 has 2 divisors, whose sum is σ = 331551422. Its totient is φ = 331551420.

The previous prime is 331551401. The next prime is 331551439. The reversal of 331551421 is 124155133.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 329023321 + 2528100 = 18139^2 + 1590^2 .

It is an emirp because it is prime and its reverse (124155133) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 331551421 - 2¹⁵ = 331518653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (331551401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165775710 + 165775711.

It is an arithmetic number, because the mean of its divisors is an integer number (165775711).

Almost surely, 2^331551421 is an apocalyptic number.

It is an amenable number.

331551421 is a deficient number, since it is larger than the sum of its proper divisors (1).

331551421 is an equidigital number, since it uses as much as digits as its factorization.

331551421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1800, while the sum is 25.

The square root of 331551421 is about 18208.5535120174. The cubic root of 331551421 is about 692.1235572139.

The spelling of 331551421 in words is "three hundred thirty-one million, five hundred fifty-one thousand, four hundred twenty-one".