491553431 has 2 divisors, whose sum is σ = 491553432. Its totient is φ = 491553430.

The previous prime is 491553421. The next prime is 491553443. The reversal of 491553431 is 134355194.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 491553431 - 2¹⁸ = 491291287 is a prime.

It is a super-2 number, since 2×491553431² = 483249551055743522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 491553391 and 491553400.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491553421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245776715 + 245776716.

It is an arithmetic number, because the mean of its divisors is an integer number (245776716).

Almost surely, 2^491553431 is an apocalyptic number.

491553431 is a deficient number, since it is larger than the sum of its proper divisors (1).

491553431 is an equidigital number, since it uses as much as digits as its factorization.

491553431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32400, while the sum is 35.

The square root of 491553431 is about 22171.0042848762. The cubic root of 491553431 is about 789.2057557273.

The spelling of 491553431 in words is "four hundred ninety-one million, five hundred fifty-three thousand, four hundred thirty-one".