1201421100 has 216 divisors, whose sum is σ = 3989744640. Its totient is φ = 278396800.

The previous prime is 1201421087. The next prime is 1201421113. The reversal of 1201421100 is 11241021.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1201421087) and next prime (1201421113).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 834181 + ... + 835619.

It is an arithmetic number, because the mean of its divisors is an integer number (18471040).

Almost surely, 2^1201421100 is an apocalyptic number.

1201421100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1201421100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1994872320).

1201421100 is an abundant number, since it is smaller than the sum of its proper divisors (2788323540).

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

1201421100 is a wasteful number, since it uses less digits than its factorization.

1201421100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1501 (or 1483 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 1201421100 is about 34661.5218938811. The cubic root of 1201421100 is about 1063.0778881702.

Adding to 1201421100 its reverse (11241021), we get a palindrome (1212662121).

The spelling of 1201421100 in words is "one billion, two hundred one million, four hundred twenty-one thousand, one hundred".