155821437140 has 12 divisors (see below), whose sum is σ = 327225018036. Its totient is φ = 62328574848.

The previous prime is 155821437133. The next prime is 155821437143. The reversal of 155821437140 is 41734128551.

It can be written as a sum of positive squares in 2 ways, for example, as 113674168336 + 42147268804 = 337156^2 + 205298^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155821437143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3895535909 + ... + 3895535948.

It is an arithmetic number, because the mean of its divisors is an integer number (27268751503).

Almost surely, 2^155821437140 is an apocalyptic number.

155821437140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

155821437140 is an abundant number, since it is smaller than the sum of its proper divisors (171403580896).

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

155821437140 is a wasteful number, since it uses less digits than its factorization.

155821437140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7791071866 (or 7791071864 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 41.

The spelling of 155821437140 in words is "one hundred fifty-five billion, eight hundred twenty-one million, four hundred thirty-seven thousand, one hundred forty".