802621421 has 6 divisors (see below), whose sum is σ = 933661710. Its totient is φ = 687961176.

The previous prime is 802621399. The next prime is 802621439. The reversal of 802621421 is 124126208.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 795804100 + 6817321 = 28210^2 + 2611^2 .

It is a de Polignac number, because none of the positive numbers 2^k-802621421 is a prime.

It is a super-2 number, since 2×802621421² = 1288402290896118482, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (802621441) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8189966 + ... + 8190063.

It is an arithmetic number, because the mean of its divisors is an integer number (155610285).

Almost surely, 2^802621421 is an apocalyptic number.

It is an amenable number.

802621421 is a deficient number, since it is larger than the sum of its proper divisors (131040289).

802621421 is a wasteful number, since it uses less digits than its factorization.

802621421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16380043 (or 16380036 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 802621421 is about 28330.5739617114. The cubic root of 802621421 is about 929.3306244276.

Adding to 802621421 its reverse (124126208), we get a palindrome (926747629).

The spelling of 802621421 in words is "eight hundred two million, six hundred twenty-one thousand, four hundred twenty-one".