604999991 has 4 divisors (see below), whose sum is σ = 605107800. Its totient is φ = 604892184.

The previous prime is 604999979. The next prime is 605000003. The reversal of 604999991 is 199999406.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 199999406 = 2 ⋅99999703.

It is an interprime number because it is at equal distance from previous prime (604999979) and next prime (605000003).

It is a cyclic number.

It is not a de Polignac number, because 604999991 - 2²⁶ = 537891127 is a prime.

It is a super-2 number, since 2×604999991² = 732049978220000162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (604999951) 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, 44996 + ... + 56873.

It is an arithmetic number, because the mean of its divisors is an integer number (151276950).

Almost surely, 2^604999991 is an apocalyptic number.

604999991 is a deficient number, since it is larger than the sum of its proper divisors (107809).

604999991 is a wasteful number, since it uses less digits than its factorization.

604999991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107808.

The product of its (nonzero) digits is 1417176, while the sum is 56.

The square root of 604999991 is about 24596.7475695467. The cubic root of 604999991 is about 845.7690516176.

The spelling of 604999991 in words is "six hundred four million, nine hundred ninety-nine thousand, nine hundred ninety-one".