420761721 has 8 divisors (see below), whose sum is σ = 574699104. Its totient is φ = 273666080.

The previous prime is 420761717. The next prime is 420761723. The reversal of 420761721 is 127167024.

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

It is a cyclic number.

It is not a de Polignac number, because 420761721 - 2² = 420761717 is a prime.

It is not an unprimeable number, because it can be changed into a prime (420761723) 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, 1710291 + ... + 1710536.

It is an arithmetic number, because the mean of its divisors is an integer number (71837388).

Almost surely, 2^420761721 is an apocalyptic number.

420761721 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

420761721 is a deficient number, since it is larger than the sum of its proper divisors (153937383).

420761721 is a wasteful number, since it uses less digits than its factorization.

420761721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3420871.

The product of its (nonzero) digits is 4704, while the sum is 30.

The square root of 420761721 is about 20512.4772029124. The cubic root of 420761721 is about 749.3396979500.

The spelling of 420761721 in words is "four hundred twenty million, seven hundred sixty-one thousand, seven hundred twenty-one".