840424531 has 8 divisors (see below), whose sum is σ = 895624704. Its totient is φ = 786779400.

The previous prime is 840424523. The next prime is 840424547. The reversal of 840424531 is 135424048.

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

It is not a de Polignac number, because 840424531 - 2³ = 840424523 is a prime.

It is a super-2 number, since 2×840424531² = 1412626784613139922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 840424493 and 840424502.

It is not an unprimeable number, because it can be changed into a prime (840424591) 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, 387645 + ... + 389806.

It is an arithmetic number, because the mean of its divisors is an integer number (111953088).

Almost surely, 2^840424531 is an apocalyptic number.

840424531 is a deficient number, since it is larger than the sum of its proper divisors (55200173).

840424531 is a wasteful number, since it uses less digits than its factorization.

840424531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 777521.

The product of its (nonzero) digits is 15360, while the sum is 31.

The square root of 840424531 is about 28990.0764228037. The cubic root of 840424531 is about 943.6977222566.

Adding to 840424531 its reverse (135424048), we get a palindrome (975848579).

The spelling of 840424531 in words is "eight hundred forty million, four hundred twenty-four thousand, five hundred thirty-one".