1421343661 has 2 divisors, whose sum is σ = 1421343662. Its totient is φ = 1421343660.

The previous prime is 1421343643. The next prime is 1421343683. The reversal of 1421343661 is 1663431241.

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., 859369225 + 561974436 = 29315^2 + 23706^2 .

It is an emirp because it is prime and its reverse (1663431241) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1421343661 - 2¹⁵ = 1421310893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1421343691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 710671830 + 710671831.

It is an arithmetic number, because the mean of its divisors is an integer number (710671831).

Almost surely, 2^1421343661 is an apocalyptic number.

It is an amenable number.

1421343661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1421343661 is an equidigital number, since it uses as much as digits as its factorization.

1421343661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 31.

The square root of 1421343661 is about 37700.7116776328. The cubic root of 1421343661 is about 1124.3452746101.

The spelling of 1421343661 in words is "one billion, four hundred twenty-one million, three hundred forty-three thousand, six hundred sixty-one".