391242261942 has 160 divisors (see below), whose sum is σ = 1024275067200. Its totient is φ = 111573987840.

The previous prime is 391242261931. The next prime is 391242261973. The reversal of 391242261942 is 249162242193.

391242261942 is a `hidden beast` number, since 3 + 9 + 1 + 2 + 4 + 22 + 619 + 4 + 2 = 666.

It is a super-2 number, since 2×391242261942² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 30943942 + ... + 30956582.

It is an arithmetic number, because the mean of its divisors is an integer number (6401719170).

Almost surely, 2^391242261942 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 391242261942, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (512137533600).

391242261942 is an abundant number, since it is smaller than the sum of its proper divisors (633032805258).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

391242261942 is a wasteful number, since it uses less digits than its factorization.

391242261942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13233 (or 13210 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The spelling of 391242261942 in words is "three hundred ninety-one billion, two hundred forty-two million, two hundred sixty-one thousand, nine hundred forty-two".