20687867475 has 48 divisors (see below), whose sum is σ = 37335419904. Its totient is φ = 10024560000.

The previous prime is 20687867423. The next prime is 20687867507. The reversal of 20687867475 is 57476878602.

It is a happy number.

It is not a de Polignac number, because 20687867475 - 2⁶ = 20687867411 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1603149 + ... + 1616001.

It is an arithmetic number, because the mean of its divisors is an integer number (777821248).

Almost surely, 2^20687867475 is an apocalyptic number.

20687867475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20687867475 is a deficient number, since it is larger than the sum of its proper divisors (16647552429).

20687867475 is a wasteful number, since it uses less digits than its factorization.

20687867475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14828 (or 14823 counting only the distinct ones).

The product of its (nonzero) digits is 31610880, while the sum is 60.

The spelling of 20687867475 in words is "twenty billion, six hundred eighty-seven million, eight hundred sixty-seven thousand, four hundred seventy-five".