420072521 has 4 divisors (see below), whose sum is σ = 458260944. Its totient is φ = 381884100.

The previous prime is 420072517. The next prime is 420072557. The reversal of 420072521 is 125270024.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 420072521 - 2² = 420072517 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (420072421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19094195 + ... + 19094216.

It is an arithmetic number, because the mean of its divisors is an integer number (114565236).

Almost surely, 2^420072521 is an apocalyptic number.

It is an amenable number.

420072521 is a deficient number, since it is larger than the sum of its proper divisors (38188423).

420072521 is a wasteful number, since it uses less digits than its factorization.

420072521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38188422.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 420072521 is about 20495.6707867784. The cubic root of 420072521 is about 748.9303394567.

The spelling of 420072521 in words is "four hundred twenty million, seventy-two thousand, five hundred twenty-one".