61569776640 has 352 divisors, whose sum is σ = 209238117120. Its totient is φ = 15408562176.

The previous prime is 61569776617. The next prime is 61569776689. The reversal of 61569776640 is 4667796516.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (57).

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, 32976987 + ... + 32978853.

Almost surely, 2^61569776640 is an apocalyptic number.

61569776640 is a gapful number since it is divisible by the number (60) 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 61569776640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104619058560).

61569776640 is an abundant number, since it is smaller than the sum of its proper divisors (147668340480).

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

61569776640 is a wasteful number, since it uses less digits than its factorization.

61569776640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2027 (or 2009 counting only the distinct ones).

The product of its (nonzero) digits is 11430720, while the sum is 57.

The spelling of 61569776640 in words is "sixty-one billion, five hundred sixty-nine million, seven hundred seventy-six thousand, six hundred forty".