420040111125521 has 16 divisors (see below), whose sum is σ = 460120700005200. Its totient is φ = 381669705811968.

The previous prime is 420040111125517. The next prime is 420040111125553. The reversal of 420040111125521 is 125521111040024.

It can be written as a sum of positive squares in 8 ways, for example, as 41835282720400 + 378204828405121 = 6468020^2 + 19447489^2 .

It is a cyclic number.

It is not a de Polignac number, because 420040111125521 - 2² = 420040111125517 is a prime.

It is a super-2 number, since 2×420040111125521² (a number of 30 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (420040111925521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27241826 + ... + 39776843.

It is an arithmetic number, because the mean of its divisors is an integer number (28757543750325).

Almost surely, 2^{420040111125521} is an apocalyptic number.

It is an amenable number.

420040111125521 is a deficient number, since it is larger than the sum of its proper divisors (40080588879679).

420040111125521 is a wasteful number, since it uses less digits than its factorization.

420040111125521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67031428.

The product of its (nonzero) digits is 3200, while the sum is 29.

Adding to 420040111125521 its reverse (125521111040024), we get a palindrome (545561222165545).

The spelling of 420040111125521 in words is "four hundred twenty trillion, forty billion, one hundred eleven million, one hundred twenty-five thousand, five hundred twenty-one".