51909489 has 6 divisors (see below), whose sum is σ = 74980386. Its totient is φ = 34606320.

The previous prime is 51909467. The next prime is 51909499. The reversal of 51909489 is 98490915.

It can be written as a sum of positive squares in only one way, i.e., 33350625 + 18558864 = 5775^2 + 4308^2 .

It is not a de Polignac number, because 51909489 - 2⁸ = 51909233 is a prime.

It is a super-2 number, since 2×51909489² = 5389190096482242, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51909499) 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, 2883852 + ... + 2883869.

It is an arithmetic number, because the mean of its divisors is an integer number (12496731).

Almost surely, 2^51909489 is an apocalyptic number.

It is an amenable number.

51909489 is a deficient number, since it is larger than the sum of its proper divisors (23070897).

51909489 is a wasteful number, since it uses less digits than its factorization.

51909489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5767727 (or 5767724 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The square root of 51909489 is about 7204.8240089540. The cubic root of 51909489 is about 373.0344300936.

The spelling of 51909489 in words is "fifty-one million, nine hundred nine thousand, four hundred eighty-nine".