51221415000 has 480 divisors, whose sum is σ = 187569708480. Its totient is φ = 11618208000.

The previous prime is 51221414999. The next prime is 51221415001. The reversal of 51221415000 is 51412215.

It is an interprime number because it is at equal distance from previous prime (51221414999) and next prime (51221415001).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51221415001) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 166844847 + ... + 166845153.

It is an arithmetic number, because the mean of its divisors is an integer number (390770226).

Almost surely, 2^51221415000 is an apocalyptic number.

51221415000 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 51221415000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93784854240).

51221415000 is an abundant number, since it is smaller than the sum of its proper divisors (136348293480).

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

51221415000 is a wasteful number, since it uses less digits than its factorization.

51221415000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 577 (or 551 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 21.

Adding to 51221415000 its reverse (51412215), we get a palindrome (51272827215).

The spelling of 51221415000 in words is "fifty-one billion, two hundred twenty-one million, four hundred fifteen thousand".