611981664 has 192 divisors, whose sum is σ = 1962455040. Its totient is φ = 163215360.

The previous prime is 611981653. The next prime is 611981681. The reversal of 611981664 is 466189116.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 603622 + ... + 604634.

It is an arithmetic number, because the mean of its divisors is an integer number (10221120).

Almost surely, 2^611981664 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 611981664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (981227520).

611981664 is an abundant number, since it is smaller than the sum of its proper divisors (1350473376).

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

611981664 is a wasteful number, since it uses less digits than its factorization.

611981664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1093 (or 1085 counting only the distinct ones).

The product of its digits is 62208, while the sum is 42.

The square root of 611981664 is about 24738.2631564950. The cubic root of 611981664 is about 849.0099957064.

The spelling of 611981664 in words is "six hundred eleven million, nine hundred eighty-one thousand, six hundred sixty-four".