821219031 has 12 divisors (see below), whose sum is σ = 1213792008. Its totient is φ = 534747024.

The previous prime is 821219023. The next prime is 821219059. The reversal of 821219031 is 130912128.

It is not a de Polignac number, because 821219031 - 2³ = 821219023 is a prime.

It is a super-2 number, since 2×821219031² = 1348801393753157922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 821218986 and 821219004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821219011) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1060620 + ... + 1061393.

It is an arithmetic number, because the mean of its divisors is an integer number (101149334).

Almost surely, 2^821219031 is an apocalyptic number.

821219031 is a deficient number, since it is larger than the sum of its proper divisors (392572977).

821219031 is a wasteful number, since it uses less digits than its factorization.

821219031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2122062 (or 2122059 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 821219031 is about 28656.9194262049. The cubic root of 821219031 is about 936.4537542154.

The spelling of 821219031 in words is "eight hundred twenty-one million, two hundred nineteen thousand, thirty-one".