842978997 has 18 divisors (see below), whose sum is σ = 1416434838. Its totient is φ = 481702032.

The previous prime is 842978993. The next prime is 842979013. The reversal of 842978997 is 799879248.

It can be written as a sum of positive squares in only one way, i.e., 841058001 + 1920996 = 29001^2 + 1386^2 .

It is not a de Polignac number, because 842978997 - 2² = 842978993 is a prime.

It is a super-2 number, since 2×842978997² = 1421227178766252018, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (842978993) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 955318 + ... + 956199.

Almost surely, 2^842978997 is an apocalyptic number.

It is an amenable number.

842978997 is a deficient number, since it is larger than the sum of its proper divisors (573455841).

842978997 is a wasteful number, since it uses less digits than its factorization.

842978997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1911537 (or 1911527 counting only the distinct ones).

The product of its digits is 18289152, while the sum is 63.

The square root of 842978997 is about 29034.1005887904. The cubic root of 842978997 is about 944.6528766233.

The spelling of 842978997 in words is "eight hundred forty-two million, nine hundred seventy-eight thousand, nine hundred ninety-seven".