51690000 has 100 divisors (see below), whose sum is σ = 166959056. Its totient is φ = 13776000.

The previous prime is 51689987. The next prime is 51690011. The reversal of 51690000 is 9615.

It is a tau number, because it is divible by the number of its divisors (100).

It is a super-2 number, since 2×51690000² = 5343712200000000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 29139 + ... + 30861.

Almost surely, 2^51690000 is an apocalyptic number.

51690000 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51690000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83479528).

51690000 is an abundant number, since it is smaller than the sum of its proper divisors (115269056).

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

51690000 is a wasteful number, since it uses less digits than its factorization.

51690000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1754 (or 1733 counting only the distinct ones).

The product of its (nonzero) digits is 270, while the sum is 21.

The square root of 51690000 is about 7189.5757872075. The cubic root of 51690000 is about 372.5079198953.

Adding to 51690000 its reverse (9615), we get a palindrome (51699615).

The spelling of 51690000 in words is "fifty-one million, six hundred ninety thousand".