31420420878 has 128 divisors (see below), whose sum is σ = 83229696000. Its totient is φ = 7660448640.

The previous prime is 31420420873. The next prime is 31420420891. The reversal of 31420420878 is 87802402413.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31420420873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 940383 + ... + 973221.

It is an arithmetic number, because the mean of its divisors is an integer number (650232000).

Almost surely, 2^31420420878 is an apocalyptic number.

31420420878 is a gapful number since it is divisible by the number (38) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 31420420878, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41614848000).

31420420878 is an abundant number, since it is smaller than the sum of its proper divisors (51809275122).

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

31420420878 is a wasteful number, since it uses less digits than its factorization.

31420420878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32990.

The product of its (nonzero) digits is 86016, while the sum is 39.

The spelling of 31420420878 in words is "thirty-one billion, four hundred twenty million, four hundred twenty thousand, eight hundred seventy-eight".