20720695437 has 24 divisors (see below), whose sum is σ = 32713282784. Its totient is φ = 12560876064.

The previous prime is 20720695427. The next prime is 20720695441. The reversal of 20720695437 is 73459602702.

20720695437 is a `hidden beast` number, since 2 + 0 + 7 + 206 + 9 + 5 + 437 = 666.

It is not a de Polignac number, because 20720695437 - 2¹⁴ = 20720679053 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20720695392 and 20720695401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20720695427) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1313803 + ... + 1329480.

Almost surely, 2^20720695437 is an apocalyptic number.

It is an amenable number.

20720695437 is a deficient number, since it is larger than the sum of its proper divisors (11992587347).

20720695437 is a wasteful number, since it uses less digits than its factorization.

20720695437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2643369 (or 2643366 counting only the distinct ones).

The product of its (nonzero) digits is 635040, while the sum is 45.

The spelling of 20720695437 in words is "twenty billion, seven hundred twenty million, six hundred ninety-five thousand, four hundred thirty-seven".