1742921221 has 2 divisors, whose sum is σ = 1742921222. Its totient is φ = 1742921220.

The previous prime is 1742921177. The next prime is 1742921231. The reversal of 1742921221 is 1221292471.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1395844321 + 347076900 = 37361^2 + 18630^2 .

It is a cyclic number.

It is not a de Polignac number, because 1742921221 - 2²⁷ = 1608703493 is a prime.

It is a super-2 number, since 2×1742921221² = 6075548765224261682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1742921231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 871460610 + 871460611.

It is an arithmetic number, because the mean of its divisors is an integer number (871460611).

Almost surely, 2^1742921221 is an apocalyptic number.

It is an amenable number.

1742921221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1742921221 is an equidigital number, since it uses as much as digits as its factorization.

1742921221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 31.

The square root of 1742921221 is about 41748.3080016424. The cubic root of 1742921221 is about 1203.4440920773. Note that the first 3 decimals are identical.

The spelling of 1742921221 in words is "one billion, seven hundred forty-two million, nine hundred twenty-one thousand, two hundred twenty-one".