1997136464400 has 1920 divisors, whose sum is σ = 9302238904320. Its totient is φ = 394896384000.

The previous prime is 1997136464383. The next prime is 1997136464413. The reversal of 1997136464400 is 44646317991.

1997136464400 is a `hidden beast` number, since 1 + 9 + 9 + 7 + 136 + 464 + 40 + 0 = 666.

It is a super-2 number, since 2×1997136464400² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 1446151710 + ... + 1446153090.

It is an arithmetic number, because the mean of its divisors is an integer number (4844916096).

Almost surely, 2^{1997136464400} is an apocalyptic number.

1997136464400 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 1997136464400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4651119452160).

1997136464400 is an abundant number, since it is smaller than the sum of its proper divisors (7305102439920).

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

1997136464400 is a wasteful number, since it uses less digits than its factorization.

1997136464400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1510 (or 1493 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 54.

The spelling of 1997136464400 in words is "one trillion, nine hundred ninety-seven billion, one hundred thirty-six million, four hundred sixty-four thousand, four hundred".