1257221741 has 2 divisors, whose sum is σ = 1257221742. Its totient is φ = 1257221740.

The previous prime is 1257221711. The next prime is 1257221747. The reversal of 1257221741 is 1471227521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 984641641 + 272580100 = 31379^2 + 16510^2 .

It is a cyclic number.

It is not a de Polignac number, because 1257221741 - 2⁶ = 1257221677 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1257221698 and 1257221707.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1257221747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628610870 + 628610871.

It is an arithmetic number, because the mean of its divisors is an integer number (628610871).

Almost surely, 2^1257221741 is an apocalyptic number.

It is an amenable number.

1257221741 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257221741 is an equidigital number, since it uses as much as digits as its factorization.

1257221741 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7840, while the sum is 32.

The square root of 1257221741 is about 35457.3228120793. The cubic root of 1257221741 is about 1079.2878652952.

The spelling of 1257221741 in words is "one billion, two hundred fifty-seven million, two hundred twenty-one thousand, seven hundred forty-one".