1891149518990 has 128 divisors (see below), whose sum is σ = 3778195415040. Its totient is φ = 678320742528.

The previous prime is 1891149518987. The next prime is 1891149519029. The reversal of 1891149518990 is 998159411981.

It is a super-2 number, since 2×1891149518990² (a number of 25 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 63 ways as a sum of consecutive naturals, for example, 571860917 + ... + 571864223.

It is an arithmetic number, because the mean of its divisors is an integer number (29517151680).

Almost surely, 2^{1891149518990} is an apocalyptic number.

1891149518990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1891149518990 is a deficient number, since it is larger than the sum of its proper divisors (1887045896050).

1891149518990 is a wasteful number, since it uses less digits than its factorization.

1891149518990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4686.

The product of its (nonzero) digits is 8398080, while the sum is 65.

The spelling of 1891149518990 in words is "one trillion, eight hundred ninety-one billion, one hundred forty-nine million, five hundred eighteen thousand, nine hundred ninety".