101781090 has 64 divisors (see below), whose sum is σ = 273110400. Its totient is φ = 26972352.

The previous prime is 101781089. The next prime is 101781109. The reversal of 101781090 is 90187101.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 45621 + ... + 47799.

It is an arithmetic number, because the mean of its divisors is an integer number (4267350).

Almost surely, 2^101781090 is an apocalyptic number.

101781090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 101781090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (136555200).

101781090 is an abundant number, since it is smaller than the sum of its proper divisors (171329310).

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

101781090 is a wasteful number, since it uses less digits than its factorization.

101781090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2368 (or 2362 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 27.

The square root of 101781090 is about 10088.6614572995. The cubic root of 101781090 is about 466.8983786941.

The spelling of 101781090 in words is "one hundred one million, seven hundred eighty-one thousand, ninety".