51221343340 has 24 divisors (see below), whose sum is σ = 107656727472. Its totient is φ = 20471031360.

The previous prime is 51221343323. The next prime is 51221343359. The reversal of 51221343340 is 4334312215.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 51221343299 and 51221343308.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1070119 + ... + 1116958.

It is an arithmetic number, because the mean of its divisors is an integer number (4485696978).

Almost surely, 2^51221343340 is an apocalyptic number.

It is an amenable number.

51221343340 is an abundant number, since it is smaller than the sum of its proper divisors (56435384132).

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

51221343340 is a wasteful number, since it uses less digits than its factorization.

51221343340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2188257 (or 2188255 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 28.

Adding to 51221343340 its reverse (4334312215), we get a palindrome (55555655555).

The spelling of 51221343340 in words is "fifty-one billion, two hundred twenty-one million, three hundred forty-three thousand, three hundred forty".