77531989 has 8 divisors (see below), whose sum is σ = 81881280. Its totient is φ = 73209600.

The previous prime is 77531963. The next prime is 77532029. The reversal of 77531989 is 98913577.

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

It is a cyclic number.

It is not a de Polignac number, because 77531989 - 2⁹ = 77531477 is a prime.

It is a super-2 number, since 2×77531989² = 12022418636592242, 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 (77531939) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 652 + ... + 12469.

It is an arithmetic number, because the mean of its divisors is an integer number (10235160).

Almost surely, 2^77531989 is an apocalyptic number.

It is an amenable number.

77531989 is a deficient number, since it is larger than the sum of its proper divisors (4349291).

77531989 is a wasteful number, since it uses less digits than its factorization.

77531989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13451.

The product of its digits is 476280, while the sum is 49.

The square root of 77531989 is about 8805.2250964981. The cubic root of 77531989 is about 426.4096014843.

The spelling of 77531989 in words is "seventy-seven million, five hundred thirty-one thousand, nine hundred eighty-nine".