155401431531 has 4 divisors (see below), whose sum is σ = 207201908712. Its totient is φ = 103600954352.

The previous prime is 155401431527. The next prime is 155401431533. The reversal of 155401431531 is 135134104551.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 155401431531 - 2² = 155401431527 is a prime.

It is a super-2 number, since 2×155401431531² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 155401431492 and 155401431501.

It is not an unprimeable number, because it can be changed into a prime (155401431533) 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, 25900238586 + ... + 25900238591.

It is an arithmetic number, because the mean of its divisors is an integer number (51800477178).

Almost surely, 2^155401431531 is an apocalyptic number.

155401431531 is a deficient number, since it is larger than the sum of its proper divisors (51800477181).

155401431531 is an equidigital number, since it uses as much as digits as its factorization.

155401431531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51800477180.

The product of its (nonzero) digits is 18000, while the sum is 33.

The spelling of 155401431531 in words is "one hundred fifty-five billion, four hundred one million, four hundred thirty-one thousand, five hundred thirty-one".