1966947840 has 640 divisors, whose sum is σ = 8249472000. Its totient is φ = 437944320.

The previous prime is 1966947781. The next prime is 1966947859. The reversal of 1966947840 is 487496691.

It is a tau number, because it is divible by the number of its divisors (640).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9884061 + ... + 9884259.

It is an arithmetic number, because the mean of its divisors is an integer number (12889800).

Almost surely, 2^1966947840 is an apocalyptic number.

1966947840 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 1966947840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4124736000).

1966947840 is an abundant number, since it is smaller than the sum of its proper divisors (6282524160).

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

1966947840 is a wasteful number, since it uses less digits than its factorization.

1966947840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255 (or 233 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The square root of 1966947840 is about 44350.2856811543. The cubic root of 1966947840 is about 1252.9419430781.

The spelling of 1966947840 in words is "one billion, nine hundred sixty-six million, nine hundred forty-seven thousand, eight hundred forty".