1249021900 has 108 divisors (see below), whose sum is σ = 3239066992. Its totient is φ = 409495680.

The previous prime is 1249021889. The next prime is 1249021919. The reversal of 1249021900 is 91209421.

It is a happy number.

It is a super-2 number, since 2×1249021900² = 3120111413359220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 368614 + ... + 371986.

Almost surely, 2^1249021900 is an apocalyptic number.

1249021900 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 1249021900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1619533496).

1249021900 is an abundant number, since it is smaller than the sum of its proper divisors (1990045092).

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

1249021900 is a wasteful number, since it uses less digits than its factorization.

1249021900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3440 (or 3410 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 1249021900 is about 35341.5039295161. The cubic root of 1249021900 is about 1076.9363046910.

The spelling of 1249021900 in words is "one billion, two hundred forty-nine million, twenty-one thousand, nine hundred".