65421421956 has 240 divisors, whose sum is σ = 194163298560. Its totient is φ = 19034196480.

The previous prime is 65421421921. The next prime is 65421421957. The reversal of 65421421956 is 65912412456.

65421421956 is a `hidden beast` number, since 6 + 5 + 421 + 4 + 219 + 5 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (65421421957) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 8874240 + ... + 8881608.

It is an arithmetic number, because the mean of its divisors is an integer number (809013744).

Almost surely, 2^65421421956 is an apocalyptic number.

65421421956 is a gapful number since it is divisible by the number (66) 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 65421421956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97081649280).

65421421956 is an abundant number, since it is smaller than the sum of its proper divisors (128741876604).

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

65421421956 is a wasteful number, since it uses less digits than its factorization.

65421421956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7496 (or 7485 counting only the distinct ones).

The product of its digits is 518400, while the sum is 45.

The spelling of 65421421956 in words is "sixty-five billion, four hundred twenty-one million, four hundred twenty-one thousand, nine hundred fifty-six".