81219431462400 has 7200 divisors, whose sum is σ = 408192524720640. Its totient is φ = 15736799232000.

The previous prime is 81219431462363. The next prime is 81219431462431. The reversal of 81219431462400 is 426413491218.

81219431462400 is a `hidden beast` number, since 8 + 1 + 2 + 1 + 9 + 4 + 3 + 14 + 624 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (7200).

It is a super-2 number, since 2×81219431462400² (a number of 29 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 an unprimeable number.

It is a polite number, since it can be written in 719 ways as a sum of consecutive naturals, for example, 912577881556 + ... + 912577881644.

Almost surely, 2^{81219431462400} is an apocalyptic number.

81219431462400 is a gapful number since it is divisible by the number (80) 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 81219431462400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (204096262360320).

81219431462400 is an abundant number, since it is smaller than the sum of its proper divisors (326973093258240).

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

81219431462400 is a wasteful number, since it uses less digits than its factorization.

81219431462400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248 (or 211 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The spelling of 81219431462400 in words is "eighty-one trillion, two hundred nineteen billion, four hundred thirty-one million, four hundred sixty-two thousand, four hundred".