20210551491 has 16 divisors (see below), whose sum is σ = 29023142400. Its totient is φ = 12436035360.

The previous prime is 20210551447. The next prime is 20210551519. The reversal of 20210551491 is 19415501202.

It is not a de Polignac number, because 20210551491 - 2²⁷ = 20076333763 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20210551411) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 524710 + ... + 561908.

It is an arithmetic number, because the mean of its divisors is an integer number (1813946400).

Almost surely, 2^20210551491 is an apocalyptic number.

20210551491 is a deficient number, since it is larger than the sum of its proper divisors (8812590909).

20210551491 is a wasteful number, since it uses less digits than its factorization.

20210551491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51146.

The product of its (nonzero) digits is 3600, while the sum is 30.

The spelling of 20210551491 in words is "twenty billion, two hundred ten million, five hundred fifty-one thousand, four hundred ninety-one".