18911945460 has 48 divisors (see below), whose sum is σ = 56068358976. Its totient is φ = 4746527232.

The previous prime is 18911945449. The next prime is 18911945489. The reversal of 18911945460 is 6454911981.

It is a super-2 number, since 2×18911945460² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9269542 + ... + 9271581.

It is an arithmetic number, because the mean of its divisors is an integer number (1168090812).

Almost surely, 2^18911945460 is an apocalyptic number.

18911945460 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18911945460 is an abundant number, since it is smaller than the sum of its proper divisors (37156413516).

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

18911945460 is a wasteful number, since it uses less digits than its factorization.

18911945460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18541152 (or 18541150 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 48.

It can be divided in two parts, 1891 and 1945460, that added together give a triangular number (1947351 = T₁₉₇₃).

The spelling of 18911945460 in words is "eighteen billion, nine hundred eleven million, nine hundred forty-five thousand, four hundred sixty".