121606621 has 2 divisors, whose sum is σ = 121606622. Its totient is φ = 121606620.

The previous prime is 121606619. The next prime is 121606633. The reversal of 121606621 is 126606121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75516100 + 46090521 = 8690^2 + 6789^2 .

It is an emirp because it is prime and its reverse (126606121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121606621 - 2¹ = 121606619 is a prime.

Together with 121606619, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121606921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60803310 + 60803311.

It is an arithmetic number, because the mean of its divisors is an integer number (60803311).

Almost surely, 2^121606621 is an apocalyptic number.

It is an amenable number.

121606621 is a deficient number, since it is larger than the sum of its proper divisors (1).

121606621 is an equidigital number, since it uses as much as digits as its factorization.

121606621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 121606621 is about 11027.5392087265. The cubic root of 121606621 is about 495.4339234884.

It can be divided in two parts, 12160 and 6621, that added together give a palindrome (18781).

The spelling of 121606621 in words is "one hundred twenty-one million, six hundred six thousand, six hundred twenty-one".