251151155440 has 40 divisors (see below), whose sum is σ = 583961003568. Its totient is φ = 100454515200.

The previous prime is 251151155389. The next prime is 251151155449. The reversal of 251151155440 is 44551151152.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 251151155396 and 251151155405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251151155449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1419915 + ... + 1586965.

Almost surely, 2^251151155440 is an apocalyptic number.

251151155440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251151155440 is an abundant number, since it is smaller than the sum of its proper divisors (332809848128).

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

251151155440 is a wasteful number, since it uses less digits than its factorization.

251151155440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185857 (or 185851 counting only the distinct ones).

The product of its (nonzero) digits is 20000, while the sum is 34.

The spelling of 251151155440 in words is "two hundred fifty-one billion, one hundred fifty-one million, one hundred fifty-five thousand, four hundred forty".