20750721734 has 4 divisors (see below), whose sum is σ = 31126082604. Its totient is φ = 10375360866.

The previous prime is 20750721727. The next prime is 20750721757. The reversal of 20750721734 is 43712705702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 43712705702 = 2 ⋅21856352851.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5187680432 + ... + 5187680435.

It is an arithmetic number, because the mean of its divisors is an integer number (7781520651).

Almost surely, 2^20750721734 is an apocalyptic number.

20750721734 is a deficient number, since it is larger than the sum of its proper divisors (10375360870).

20750721734 is a wasteful number, since it uses less digits than its factorization.

20750721734 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10375360869.

The product of its (nonzero) digits is 82320, while the sum is 38.

The spelling of 20750721734 in words is "twenty billion, seven hundred fifty million, seven hundred twenty-one thousand, seven hundred thirty-four".