1640429772800 has 1344 divisors, whose sum is σ = 5406043991040. Its totient is φ = 479597690880.

The previous prime is 1640429772799. The next prime is 1640429772809. The reversal of 1640429772800 is 82779240461.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (50).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640429772809) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 18431795156 + ... + 18431795244.

It is an arithmetic number, because the mean of its divisors is an integer number (4022354160).

Almost surely, 2^{1640429772800} is an apocalyptic number.

1640429772800 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 1640429772800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2703021995520).

1640429772800 is an abundant number, since it is smaller than the sum of its proper divisors (3765614218240).

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

1640429772800 is a wasteful number, since it uses less digits than its factorization.

1640429772800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211 (or 182 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 50.

The spelling of 1640429772800 in words is "one trillion, six hundred forty billion, four hundred twenty-nine million, seven hundred seventy-two thousand, eight hundred".