20687378477158 has 4 divisors (see below), whose sum is σ = 31031067715740. Its totient is φ = 10343689238578.

The previous prime is 20687378477153. The next prime is 20687378477179. The reversal of 20687378477158 is 85177487378602.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×20687378477158² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20687378477153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5171844619288 + ... + 5171844619291.

It is an arithmetic number, because the mean of its divisors is an integer number (7757766928935).

Almost surely, 2^{20687378477158} is an apocalyptic number.

20687378477158 is a deficient number, since it is larger than the sum of its proper divisors (10343689238582).

20687378477158 is a wasteful number, since it uses less digits than its factorization.

20687378477158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10343689238581.

The product of its (nonzero) digits is 885104640, while the sum is 73.

The spelling of 20687378477158 in words is "twenty trillion, six hundred eighty-seven billion, three hundred seventy-eight million, four hundred seventy-seven thousand, one hundred fifty-eight".