20291678534 has 4 divisors (see below), whose sum is σ = 30437517804. Its totient is φ = 10145839266.

The previous prime is 20291678531. The next prime is 20291678557. The reversal of 20291678534 is 43587619202.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20291678531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5072919632 + ... + 5072919635.

It is an arithmetic number, because the mean of its divisors is an integer number (7609379451).

It is a 1-persistent number, because it is pandigital, but 2⋅20291678534 = 40583357068 is not.

Almost surely, 2^20291678534 is an apocalyptic number.

20291678534 is a deficient number, since it is larger than the sum of its proper divisors (10145839270).

20291678534 is a wasteful number, since it uses less digits than its factorization.

20291678534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10145839269.

The product of its (nonzero) digits is 725760, while the sum is 47.

The spelling of 20291678534 in words is "twenty billion, two hundred ninety-one million, six hundred seventy-eight thousand, five hundred thirty-four".