1225191921408 has 864 divisors, whose sum is σ = 4624517753856. Its totient is φ = 302731886592.

The previous prime is 1225191921361. The next prime is 1225191921461. The reversal of 1225191921408 is 8041291915221.

1225191921408 is a `hidden beast` number, since 1 + 2 + 2 + 51 + 9 + 192 + 1 + 408 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 937407091 + ... + 937408397.

It is an arithmetic number, because the mean of its divisors is an integer number (5352451104).

Almost surely, 2^{1225191921408} is an apocalyptic number.

1225191921408 is a gapful number since it is divisible by the number (18) 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 1225191921408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2312258876928).

1225191921408 is an abundant number, since it is smaller than the sum of its proper divisors (3399325832448).

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

1225191921408 is a wasteful number, since it uses less digits than its factorization.

1225191921408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1629 (or 1612 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 45.

The spelling of 1225191921408 in words is "one trillion, two hundred twenty-five billion, one hundred ninety-one million, nine hundred twenty-one thousand, four hundred eight".