61854643840 has 64 divisors (see below), whose sum is σ = 161314117920. Its totient is φ = 22492595200.

The previous prime is 61854643831. The next prime is 61854643841. The reversal of 61854643840 is 4834645816.

61854643840 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 (64).

It is not an unprimeable number, because it can be changed into a prime (61854643841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4386046 + ... + 4400125.

Almost surely, 2^61854643840 is an apocalyptic number.

It is an amenable number.

61854643840 is an abundant number, since it is smaller than the sum of its proper divisors (99459474080).

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

61854643840 is a wasteful number, since it uses less digits than its factorization.

61854643840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8786201 (or 8786189 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 49.

The spelling of 61854643840 in words is "sixty-one billion, eight hundred fifty-four million, six hundred forty-three thousand, eight hundred forty".