1221458813640 has 384 divisors, whose sum is σ = 4440247943040. Its totient is φ = 300205357056.

The previous prime is 1221458813623. The next prime is 1221458813657. The reversal of 1221458813640 is 463188541221.

1221458813640 is a `hidden beast` number, since 1 + 2 + 2 + 1 + 4 + 588 + 1 + 3 + 64 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (1221458813623) and next prime (1221458813657).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 86296804 + ... + 86310956.

It is an arithmetic number, because the mean of its divisors is an integer number (11563145685).

Almost surely, 2^{1221458813640} is an apocalyptic number.

1221458813640 is a gapful number since it is divisible by the number (10) 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 1221458813640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2220123971520).

1221458813640 is an abundant number, since it is smaller than the sum of its proper divisors (3218789129400).

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

1221458813640 is a wasteful number, since it uses less digits than its factorization.

1221458813640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14875 (or 14859 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The spelling of 1221458813640 in words is "one trillion, two hundred twenty-one billion, four hundred fifty-eight million, eight hundred thirteen thousand, six hundred forty".