628476421 has 2 divisors, whose sum is σ = 628476422. Its totient is φ = 628476420.

The previous prime is 628476419. The next prime is 628476461. The reversal of 628476421 is 124674826.

It is a happy number.

It is an a-pointer prime, because the next prime (628476461) can be obtained adding 628476421 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 596043396 + 32433025 = 24414^2 + 5695^2 .

It is a cyclic number.

It is not a de Polignac number, because 628476421 - 2¹ = 628476419 is a prime.

It is a super-2 number, since 2×628476421² = 789965223505938482, which contains 22 as substring.

Together with 628476419, 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 (628476461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 314238210 + 314238211.

It is an arithmetic number, because the mean of its divisors is an integer number (314238211).

Almost surely, 2^628476421 is an apocalyptic number.

It is an amenable number.

628476421 is a deficient number, since it is larger than the sum of its proper divisors (1).

628476421 is an equidigital number, since it uses as much as digits as its factorization.

628476421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129024, while the sum is 40.

The square root of 628476421 is about 25069.4320039366. The cubic root of 628476421 is about 856.5702689117.

The spelling of 628476421 in words is "six hundred twenty-eight million, four hundred seventy-six thousand, four hundred twenty-one".