31773421 has 2 divisors, whose sum is σ = 31773422. Its totient is φ = 31773420.

The previous prime is 31773409. The next prime is 31773437. The reversal of 31773421 is 12437713.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31203396 + 570025 = 5586^2 + 755^2 .

It is a cyclic number.

It is not a de Polignac number, because 31773421 - 2⁵ = 31773389 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31773421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31776421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15886710 + 15886711.

It is an arithmetic number, because the mean of its divisors is an integer number (15886711).

Almost surely, 2^31773421 is an apocalyptic number.

It is an amenable number.

31773421 is a deficient number, since it is larger than the sum of its proper divisors (1).

31773421 is an equidigital number, since it uses as much as digits as its factorization.

31773421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3528, while the sum is 28.

The square root of 31773421 is about 5636.7917293439. The cubic root of 31773421 is about 316.7291187383.

The spelling of 31773421 in words is "thirty-one million, seven hundred seventy-three thousand, four hundred twenty-one".