616401 has 6 divisors (see below), whose sum is σ = 890370. Its totient is φ = 410928.

The previous prime is 616393. The next prime is 616409. The reversal of 616401 is 104616.

It is an interprime number because it is at equal distance from previous prime (616393) and next prime (616409).

It can be written as a sum of positive squares in only one way, i.e., 540225 + 76176 = 735^2 + 276^2 .

It is not a de Polignac number, because 616401 - 2³ = 616393 is a prime.

It is an Ulam number.

616401 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 616401.

It is not an unprimeable number, because it can be changed into a prime (616409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 34236 + ... + 34253.

It is an arithmetic number, because the mean of its divisors is an integer number (148395).

2⁶¹⁶⁴⁰¹ is an apocalyptic number.

It is an amenable number.

616401 is a deficient number, since it is larger than the sum of its proper divisors (273969).

616401 is a wasteful number, since it uses less digits than its factorization.

616401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68495 (or 68492 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 616401 is about 785.1120939076. The cubic root of 616401 is about 85.1048763133.

The spelling of 616401 in words is "six hundred sixteen thousand, four hundred one".