221657057 has 2 divisors, whose sum is σ = 221657058. Its totient is φ = 221657056.

The previous prime is 221657053. The next prime is 221657069. The reversal of 221657057 is 750756122.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 111175936 + 110481121 = 10544^2 + 10511^2 .

It is a cyclic number.

It is not a de Polignac number, because 221657057 - 2² = 221657053 is a prime.

It is not a weakly prime, because it can be changed into another prime (221657053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110828528 + 110828529.

It is an arithmetic number, because the mean of its divisors is an integer number (110828529).

Almost surely, 2^221657057 is an apocalyptic number.

It is an amenable number.

221657057 is a deficient number, since it is larger than the sum of its proper divisors (1).

221657057 is an equidigital number, since it uses as much as digits as its factorization.

221657057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 29400, while the sum is 35.

The square root of 221657057 is about 14888.1515642473. The cubic root of 221657057 is about 605.1929416722.

The spelling of 221657057 in words is "two hundred twenty-one million, six hundred fifty-seven thousand, fifty-seven".