61121788020 has 72 divisors (see below), whose sum is σ = 185423960904. Its totient is φ = 16297279488.

The previous prime is 61121788019. The next prime is 61121788139. The reversal of 61121788020 is 2088712116.

61121788020 is a `hidden beast` number, since 611 + 2 + 17 + 8 + 8 + 0 + 20 = 666.

61121788020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 3803682276 + 57318105744 = 61674^2 + 239412^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2380692 + ... + 2406228.

Almost surely, 2^61121788020 is an apocalyptic number.

61121788020 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61121788020 is an abundant number, since it is smaller than the sum of its proper divisors (124302172884).

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

61121788020 is a wasteful number, since it uses less digits than its factorization.

61121788020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38849 (or 38844 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 36.

The spelling of 61121788020 in words is "sixty-one billion, one hundred twenty-one million, seven hundred eighty-eight thousand, twenty".