628161901 has 4 divisors (see below), whose sum is σ = 655473312. Its totient is φ = 600850492.

The previous prime is 628161893. The next prime is 628161923. The reversal of 628161901 is 109161826.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 628161901 - 2³ = 628161893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (628161991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13655671 + ... + 13655716.

It is an arithmetic number, because the mean of its divisors is an integer number (163868328).

Almost surely, 2^628161901 is an apocalyptic number.

It is an amenable number.

628161901 is a deficient number, since it is larger than the sum of its proper divisors (27311411).

628161901 is a wasteful number, since it uses less digits than its factorization.

628161901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27311410.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 628161901 is about 25063.1582407326. The cubic root of 628161901 is about 856.4273553374.

The spelling of 628161901 in words is "six hundred twenty-eight million, one hundred sixty-one thousand, nine hundred one".