51091500 has 48 divisors (see below), whose sum is σ = 148782816. Its totient is φ = 13624000.

The previous prime is 51091483. The next prime is 51091517. The reversal of 51091500 is 519015.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (51091483) and next prime (51091517).

It is a super-2 number, since 2×51091500² = 5220682744500000, which contains 22 as substring.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 15531 + ... + 18530.

It is an arithmetic number, because the mean of its divisors is an integer number (3099642).

Almost surely, 2^51091500 is an apocalyptic number.

51091500 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

51091500 is an abundant number, since it is smaller than the sum of its proper divisors (97691316).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51091500 is a wasteful number, since it uses less digits than its factorization.

51091500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34083 (or 34071 counting only the distinct ones).

The product of its (nonzero) digits is 225, while the sum is 21.

The square root of 51091500 is about 7147.8318390964. The cubic root of 51091500 is about 371.0646230694.

The spelling of 51091500 in words is "fifty-one million, ninety-one thousand, five hundred".