101220421 has 2 divisors, whose sum is σ = 101220422. Its totient is φ = 101220420.

The previous prime is 101220377. The next prime is 101220433. The reversal of 101220421 is 124022101.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 94303521 + 6916900 = 9711^2 + 2630^2 .

It is a cyclic number.

It is not a de Polignac number, because 101220421 - 2¹¹ = 101218373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101220481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50610210 + 50610211.

It is an arithmetic number, because the mean of its divisors is an integer number (50610211).

Almost surely, 2^101220421 is an apocalyptic number.

It is an amenable number.

101220421 is a deficient number, since it is larger than the sum of its proper divisors (1).

101220421 is an equidigital number, since it uses as much as digits as its factorization.

101220421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 101220421 is about 10060.8359990609. The cubic root of 101220421 is about 466.0394843959.

Adding to 101220421 its reverse (124022101), we get a palindrome (225242522).

The spelling of 101220421 in words is "one hundred one million, two hundred twenty thousand, four hundred twenty-one".