16661337420 has 192 divisors, whose sum is σ = 57490707456. Its totient is φ = 3510881280.

The previous prime is 16661337401. The next prime is 16661337431. The reversal of 16661337420 is 2473316661.

It is a Harshad number since it is a multiple of its sum of digits (39).

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, 5955462 + ... + 5958258.

It is an arithmetic number, because the mean of its divisors is an integer number (299430768).

Almost surely, 2^16661337420 is an apocalyptic number.

16661337420 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 16661337420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28745353728).

16661337420 is an abundant number, since it is smaller than the sum of its proper divisors (40829370036).

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

16661337420 is a wasteful number, since it uses less digits than its factorization.

16661337420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3920 (or 3918 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 39.

The spelling of 16661337420 in words is "sixteen billion, six hundred sixty-one million, three hundred thirty-seven thousand, four hundred twenty".