61878539520 has 1152 divisors, whose sum is σ = 267241390080. Its totient is φ = 13257768960.

The previous prime is 61878539519. The next prime is 61878539533. The reversal of 61878539520 is 2593587816.

61878539520 is a `hidden beast` number, since 6 + 1 + 8 + 7 + 85 + 39 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 277482129 + ... + 277482351.

Almost surely, 2^61878539520 is an apocalyptic number.

61878539520 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 61878539520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133620695040).

61878539520 is an abundant number, since it is smaller than the sum of its proper divisors (205362850560).

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

61878539520 is a wasteful number, since it uses less digits than its factorization.

61878539520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328 (or 308 counting only the distinct ones).

The product of its (nonzero) digits is 3628800, while the sum is 54.

The spelling of 61878539520 in words is "sixty-one billion, eight hundred seventy-eight million, five hundred thirty-nine thousand, five hundred twenty".