1971898572 has 144 divisors (see below), whose sum is σ = 5534736480. Its totient is φ = 544416768.

The previous prime is 1971898571. The next prime is 1971898589. The reversal of 1971898572 is 2758981791.

It is not an unprimeable number, because it can be changed into a prime (1971898571) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5068954 + ... + 5069342.

It is an arithmetic number, because the mean of its divisors is an integer number (38435670).

Almost surely, 2^1971898572 is an apocalyptic number.

1971898572 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 1971898572, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2767368240).

1971898572 is an abundant number, since it is smaller than the sum of its proper divisors (3562837908).

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

1971898572 is a wasteful number, since it uses less digits than its factorization.

1971898572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680 (or 671 counting only the distinct ones).

The product of its digits is 2540160, while the sum is 57.

The square root of 1971898572 is about 44406.0645858198. The cubic root of 1971898572 is about 1253.9922645779.

It can be divided in two parts, 197189 and 8572, that added together give a triangular number (205761 = T₆₄₁).

The spelling of 1971898572 in words is "one billion, nine hundred seventy-one million, eight hundred ninety-eight thousand, five hundred seventy-two".