1000021420 has 24 divisors (see below), whose sum is σ = 2103399648. Its totient is φ = 399369600.

The previous prime is 1000021409. The next prime is 1000021489. The reversal of 1000021420 is 241200001.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 1000021397 and 1000021406.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27001 + ... + 52240.

It is an arithmetic number, because the mean of its divisors is an integer number (87641652).

Almost surely, 2^1000021420 is an apocalyptic number.

1000021420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1000021420 is an abundant number, since it is smaller than the sum of its proper divisors (1103378228).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1000021420 is a wasteful number, since it uses less digits than its factorization.

1000021420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79881 (or 79879 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 1000021420 is about 31623.1152798076. The cubic root of 1000021420 is about 1000.0071399490.

Adding to 1000021420 its reverse (241200001), we get a palindrome (1241221421).

The spelling of 1000021420 in words is "one billion, twenty-one thousand, four hundred twenty".