66401042730 has 128 divisors (see below), whose sum is σ = 184216363776. Its totient is φ = 15138816000.

The previous prime is 66401042723. The next prime is 66401042731. The reversal of 66401042730 is 3724010466.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 66401042691 and 66401042700.

It is not an unprimeable number, because it can be changed into a prime (66401042731) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8977914 + ... + 8985306.

It is an arithmetic number, because the mean of its divisors is an integer number (1439190342).

Almost surely, 2^66401042730 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66401042730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92108181888).

66401042730 is an abundant number, since it is smaller than the sum of its proper divisors (117815321046).

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

66401042730 is a wasteful number, since it uses less digits than its factorization.

66401042730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9032.

The product of its (nonzero) digits is 24192, while the sum is 33.

The spelling of 66401042730 in words is "sixty-six billion, four hundred one million, forty-two thousand, seven hundred thirty".