61421823864 has 24 divisors (see below), whose sum is σ = 166350773160. Its totient is φ = 20473941264.

The previous prime is 61421823857. The next prime is 61421823893. The reversal of 61421823864 is 46832812416.

61421823864 is a `hidden beast` number, since 61 + 421 + 82 + 38 + 64 = 666.

61421823864 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (24).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 426540372 + ... + 426540515.

It is an arithmetic number, because the mean of its divisors is an integer number (6931282215).

Almost surely, 2^61421823864 is an apocalyptic number.

It is an amenable number.

61421823864 is an abundant number, since it is smaller than the sum of its proper divisors (104928949296).

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

61421823864 is a wasteful number, since it uses less digits than its factorization.

61421823864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 853080899 (or 853080892 counting only the distinct ones).

The product of its digits is 442368, while the sum is 45.

The spelling of 61421823864 in words is "sixty-one billion, four hundred twenty-one million, eight hundred twenty-three thousand, eight hundred sixty-four".