47747221 has 2 divisors, whose sum is σ = 47747222. Its totient is φ = 47747220.

The previous prime is 47747207. The next prime is 47747233. The reversal of 47747221 is 12274774.

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., 38068900 + 9678321 = 6170^2 + 3111^2 .

It is a cyclic number.

It is not a de Polignac number, because 47747221 - 2⁷ = 47747093 is a prime.

It is a super-2 number, since 2×47747221² = 4559594226445682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (47747261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23873610 + 23873611.

It is an arithmetic number, because the mean of its divisors is an integer number (23873611).

Almost surely, 2^47747221 is an apocalyptic number.

It is an amenable number.

47747221 is a deficient number, since it is larger than the sum of its proper divisors (1).

47747221 is an equidigital number, since it uses as much as digits as its factorization.

47747221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21952, while the sum is 34.

The square root of 47747221 is about 6909.9363962340. The cubic root of 47747221 is about 362.7850371694.

The spelling of 47747221 in words is "forty-seven million, seven hundred forty-seven thousand, two hundred twenty-one".