661000061952 has 528 divisors, whose sum is σ = 2043145744640. Its totient is φ = 213324668928.

The previous prime is 661000061941. The next prime is 661000061959. The reversal of 661000061952 is 259160000166.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (661000061959) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1744063299 + ... + 1744063677.

Almost surely, 2^661000061952 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 661000061952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1021572872320).

661000061952 is an abundant number, since it is smaller than the sum of its proper divisors (1382145682688).

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

661000061952 is a wasteful number, since it uses less digits than its factorization.

661000061952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620 (or 590 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The spelling of 661000061952 in words is "six hundred sixty-one billion, sixty-one thousand, nine hundred fifty-two".