1537138644 has 24 divisors (see below), whose sum is σ = 3609506208. Its totient is φ = 509115360.

The previous prime is 1537138643. The next prime is 1537138709. The reversal of 1537138644 is 4468317351.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1537138596 and 1537138605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1537138643) 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, 406062 + ... + 409829.

It is an arithmetic number, because the mean of its divisors is an integer number (150396092).

Almost surely, 2^1537138644 is an apocalyptic number.

It is an amenable number.

1537138644 is an abundant number, since it is smaller than the sum of its proper divisors (2072367564).

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

1537138644 is a wasteful number, since it uses less digits than its factorization.

1537138644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816055 (or 816053 counting only the distinct ones).

The product of its digits is 241920, while the sum is 42.

The square root of 1537138644 is about 39206.3597392056. The cubic root of 1537138644 is about 1154.0846915227.

The spelling of 1537138644 in words is "one billion, five hundred thirty-seven million, one hundred thirty-eight thousand, six hundred forty-four".