1547391972 has 72 divisors (see below), whose sum is σ = 4205268480. Its totient is φ = 441564480.

The previous prime is 1547391971. The next prime is 1547392087. The reversal of 1547391972 is 2791937451.

It is not an unprimeable number, because it can be changed into a prime (1547391971) 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 23 ways as a sum of consecutive naturals, for example, 864054 + ... + 865842.

Almost surely, 2^1547391972 is an apocalyptic number.

1547391972 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1547391972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2102634240).

1547391972 is an abundant number, since it is smaller than the sum of its proper divisors (2657876508).

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

1547391972 is a wasteful number, since it uses less digits than its factorization.

1547391972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3281 (or 3272 counting only the distinct ones).

The product of its digits is 476280, while the sum is 48.

The square root of 1547391972 is about 39336.9034368492. The cubic root of 1547391972 is about 1156.6450754449.

The spelling of 1547391972 in words is "one billion, five hundred forty-seven million, three hundred ninety-one thousand, nine hundred seventy-two".