1271761920 has 528 divisors, whose sum is σ = 5203834272. Its totient is φ = 283115520.

The previous prime is 1271761919. The next prime is 1271761943. The reversal of 1271761920 is 291671721.

It is a happy number.

1271761920 is a `hidden beast` number, since 1 + 2 + 7 + 17 + 619 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (528).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6589344 + ... + 6589536.

Almost surely, 2^1271761920 is an apocalyptic number.

1271761920 is a gapful number since it is divisible by the number (10) 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 1271761920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2601917136).

1271761920 is an abundant number, since it is smaller than the sum of its proper divisors (3932072352).

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

1271761920 is a wasteful number, since it uses less digits than its factorization.

1271761920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 10584, while the sum is 36.

The square root of 1271761920 is about 35661.7711281983. The cubic root of 1271761920 is about 1083.4326992617.

The spelling of 1271761920 in words is "one billion, two hundred seventy-one million, seven hundred sixty-one thousand, nine hundred twenty".