221421651707 has 2 divisors, whose sum is σ = 221421651708. Its totient is φ = 221421651706.

The previous prime is 221421651589. The next prime is 221421651719. The reversal of 221421651707 is 707156124122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221421651707 - 2¹⁶ = 221421586171 is a prime.

It is not a weakly prime, because it can be changed into another prime (221421651007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110710825853 + 110710825854.

It is an arithmetic number, because the mean of its divisors is an integer number (110710825854).

Almost surely, 2^221421651707 is an apocalyptic number.

221421651707 is a deficient number, since it is larger than the sum of its proper divisors (1).

221421651707 is an equidigital number, since it uses as much as digits as its factorization.

221421651707 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 47040, while the sum is 38.

Adding to 221421651707 its reverse (707156124122), we get a palindrome (928577775829).

The spelling of 221421651707 in words is "two hundred twenty-one billion, four hundred twenty-one million, six hundred fifty-one thousand, seven hundred seven".