611206640 has 80 divisors (see below), whose sum is σ = 1559900160. Its totient is φ = 220872960.

The previous prime is 611206621. The next prime is 611206643. The reversal of 611206640 is 46602116.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (611206643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 144881 + ... + 149039.

It is an arithmetic number, because the mean of its divisors is an integer number (19498752).

Almost surely, 2^611206640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 611206640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (779950080).

611206640 is an abundant number, since it is smaller than the sum of its proper divisors (948693520).

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

611206640 is a wasteful number, since it uses less digits than its factorization.

611206640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4350 (or 4344 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 611206640 is about 24722.5937150615. The cubic root of 611206640 is about 848.6514440667.

Adding to 611206640 its reverse (46602116), we get a palindrome (657808756).

The spelling of 611206640 in words is "six hundred eleven million, two hundred six thousand, six hundred forty".