491251420279 has 4 divisors (see below), whose sum is σ = 507098240320. Its totient is φ = 475404600240.

The previous prime is 491251420249. The next prime is 491251420333. The reversal of 491251420279 is 972024152194.

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

It is a cyclic number.

It is not a de Polignac number, because 491251420279 - 2⁷ = 491251420151 is a prime.

It is a super-2 number, since 2×491251420279² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491251420229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7923409974 + ... + 7923410035.

It is an arithmetic number, because the mean of its divisors is an integer number (126774560080).

Almost surely, 2^491251420279 is an apocalyptic number.

491251420279 is a deficient number, since it is larger than the sum of its proper divisors (15846820041).

491251420279 is a wasteful number, since it uses less digits than its factorization.

491251420279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15846820040.

The product of its (nonzero) digits is 362880, while the sum is 46.

The spelling of 491251420279 in words is "four hundred ninety-one billion, two hundred fifty-one million, four hundred twenty thousand, two hundred seventy-nine".