51691671900 has 162 divisors, whose sum is σ = 178093611696. Its totient is φ = 12531288000.

The previous prime is 51691671893. The next prime is 51691671901. The reversal of 51691671900 is 917619615.

It is a super-2 number, since 2×51691671900² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51691671901) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 128436 + ... + 346235.

Almost surely, 2^51691671900 is an apocalyptic number.

51691671900 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

51691671900 is an abundant number, since it is smaller than the sum of its proper divisors (126401939796).

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

51691671900 is a wasteful number, since it uses less digits than its factorization.

51691671900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474713 (or 474692 counting only the distinct ones).

The product of its (nonzero) digits is 102060, while the sum is 45.

The spelling of 51691671900 in words is "fifty-one billion, six hundred ninety-one million, six hundred seventy-one thousand, nine hundred".