628961969 has 2 divisors, whose sum is σ = 628961970. Its totient is φ = 628961968.

The previous prime is 628961953. The next prime is 628961999. The reversal of 628961969 is 969169826.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 479829025 + 149132944 = 21905^2 + 12212^2 .

It is a cyclic number.

It is not a de Polignac number, because 628961969 - 2⁴ = 628961953 is a prime.

It is a super-2 number, since 2×628961969² = 791186316896713922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (628961999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 314480984 + 314480985.

It is an arithmetic number, because the mean of its divisors is an integer number (314480985).

Almost surely, 2^628961969 is an apocalyptic number.

It is an amenable number.

628961969 is a deficient number, since it is larger than the sum of its proper divisors (1).

628961969 is an equidigital number, since it uses as much as digits as its factorization.

628961969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2519424, while the sum is 56.

The square root of 628961969 is about 25079.1141988707. The cubic root of 628961969 is about 856.7908016722.

The spelling of 628961969 in words is "six hundred twenty-eight million, nine hundred sixty-one thousand, nine hundred sixty-nine".