609976981 has 8 divisors (see below), whose sum is σ = 631354680. Its totient is φ = 588622272.

The previous prime is 609976963. The next prime is 609976999. The reversal of 609976981 is 189679906.

It is an interprime number because it is at equal distance from previous prime (609976963) and next prime (609976999).

It can be written as a sum of positive squares in 4 ways, for example, as 133956 + 609843025 = 366^2 + 24695^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 609976981 - 2⁷ = 609976853 is a prime.

It is a super-2 number, since 2×609976981² = 744143834699748722, 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 (609976681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61911 + ... + 71083.

It is an arithmetic number, because the mean of its divisors is an integer number (78919335).

Almost surely, 2^609976981 is an apocalyptic number.

It is an amenable number.

609976981 is a deficient number, since it is larger than the sum of its proper divisors (21377699).

609976981 is a wasteful number, since it uses less digits than its factorization.

609976981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11495.

The product of its (nonzero) digits is 1469664, while the sum is 55.

The square root of 609976981 is about 24697.7120600269. The cubic root of 609976981 is about 848.0819408219.

The spelling of 609976981 in words is "six hundred nine million, nine hundred seventy-six thousand, nine hundred eighty-one".