20551501657 has 8 divisors (see below), whose sum is σ = 21182949216. Its totient is φ = 19927031712.

The previous prime is 20551501651. The next prime is 20551501679. The reversal of 20551501657 is 75610515502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20551501657 - 2¹¹ = 20551499609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20551501651) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1738423 + ... + 1750204.

It is an arithmetic number, because the mean of its divisors is an integer number (2647868652).

Almost surely, 2^20551501657 is an apocalyptic number.

It is an amenable number.

20551501657 is a deficient number, since it is larger than the sum of its proper divisors (631447559).

20551501657 is a wasteful number, since it uses less digits than its factorization.

20551501657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3488807.

The product of its (nonzero) digits is 52500, while the sum is 37.

The spelling of 20551501657 in words is "twenty billion, five hundred fifty-one million, five hundred one thousand, six hundred fifty-seven".