211631420 has 216 divisors, whose sum is σ = 621252576. Its totient is φ = 58924800.

The previous prime is 211631411. The next prime is 211631449. The reversal of 211631420 is 24136112.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 211631392 and 211631401.

It is a congruent number.

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, 6826805 + ... + 6826835.

Almost surely, 2^211631420 is an apocalyptic number.

211631420 is a gapful number since it is divisible by the number (20) 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 211631420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (310626288).

211631420 is an abundant number, since it is smaller than the sum of its proper divisors (409621156).

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

211631420 is a wasteful number, since it uses less digits than its factorization.

211631420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113 (or 69 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 211631420 is about 14547.5571832525. The cubic root of 211631420 is about 595.9274381279.

Adding to 211631420 its reverse (24136112), we get a palindrome (235767532).

The spelling of 211631420 in words is "two hundred eleven million, six hundred thirty-one thousand, four hundred twenty".