221070557 has 2 divisors, whose sum is σ = 221070558. Its totient is φ = 221070556.

The previous prime is 221070547. The next prime is 221070569. The reversal of 221070557 is 755070122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 143736121 + 77334436 = 11989^2 + 8794^2 .

It is a cyclic number.

It is not a de Polignac number, because 221070557 - 2⁴ = 221070541 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221070547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110535278 + 110535279.

It is an arithmetic number, because the mean of its divisors is an integer number (110535279).

Almost surely, 2^221070557 is an apocalyptic number.

It is an amenable number.

221070557 is a deficient number, since it is larger than the sum of its proper divisors (1).

221070557 is an equidigital number, since it uses as much as digits as its factorization.

221070557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4900, while the sum is 29.

The square root of 221070557 is about 14868.4416466555. The cubic root of 221070557 is about 604.6586941794.

The spelling of 221070557 in words is "two hundred twenty-one million, seventy thousand, five hundred fifty-seven".