20091078 has 60 divisors (see below), whose sum is σ = 52389612. Its totient is φ = 5738040.

The previous prime is 20091067. The next prime is 20091101. The reversal of 20091078 is 87019002.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 6673 + ... + 9203.

Almost surely, 2^20091078 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20091078, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26194806).

20091078 is an abundant number, since it is smaller than the sum of its proper divisors (32298534).

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

20091078 is a wasteful number, since it uses less digits than its factorization.

20091078 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2559 (or 2543 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 20091078 is about 4482.3072183865. The cubic root of 20091078 is about 271.8531773209.

The spelling of 20091078 in words is "twenty million, ninety-one thousand, seventy-eight".