621130421 has 2 divisors, whose sum is σ = 621130422. Its totient is φ = 621130420.

The previous prime is 621130409. The next prime is 621130423. The reversal of 621130421 is 124031126.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 403567921 + 217562500 = 20089^2 + 14750^2 .

It is a cyclic number.

It is not a de Polignac number, because 621130421 - 2⁶ = 621130357 is a prime.

Together with 621130423, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 621130393 and 621130402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (621130423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310565210 + 310565211.

It is an arithmetic number, because the mean of its divisors is an integer number (310565211).

Almost surely, 2^621130421 is an apocalyptic number.

It is an amenable number.

621130421 is a deficient number, since it is larger than the sum of its proper divisors (1).

621130421 is an equidigital number, since it uses as much as digits as its factorization.

621130421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 621130421 is about 24922.4882585989. The cubic root of 621130421 is about 853.2198160188.

Adding to 621130421 its reverse (124031126), we get a palindrome (745161547).

The spelling of 621130421 in words is "six hundred twenty-one million, one hundred thirty thousand, four hundred twenty-one".