3972921281 has 8 divisors (see below), whose sum is σ = 4686948864. Its totient is φ = 3295510560.

The previous prime is 3972921269. The next prime is 3972921347. The reversal of 3972921281 is 1821292793.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3972921281 is a prime.

It is a super-2 number, since 2×3972921281² = 31568207010045361922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3972921241) 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, 9153980 + ... + 9154413.

It is an arithmetic number, because the mean of its divisors is an integer number (585868608).

Almost surely, 2^3972921281 is an apocalyptic number.

3972921281 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

3972921281 is a deficient number, since it is larger than the sum of its proper divisors (714027583).

3972921281 is a wasteful number, since it uses less digits than its factorization.

3972921281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18308431.

The product of its digits is 108864, while the sum is 44.

The square root of 3972921281 is about 63031.1135947954. The cubic root of 3972921281 is about 1583.8108726990.

The spelling of 3972921281 in words is "three billion, nine hundred seventy-two million, nine hundred twenty-one thousand, two hundred eighty-one".