420290640 has 720 divisors, whose sum is σ = 1938893760. Its totient is φ = 82736640.

The previous prime is 420290639. The next prime is 420290693. The reversal of 420290640 is 46092024.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 22120551 + ... + 22120569.

It is an arithmetic number, because the mean of its divisors is an integer number (2692908).

Almost surely, 2^420290640 is an apocalyptic number.

420290640 is a gapful number since it is divisible by the number (40) 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 420290640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (969446880).

420290640 is an abundant number, since it is smaller than the sum of its proper divisors (1518603120).

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

420290640 is a wasteful number, since it uses less digits than its factorization.

420290640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 420290640 is about 20500.9911955495. The cubic root of 420290640 is about 749.0599422141.

The spelling of 420290640 in words is "four hundred twenty million, two hundred ninety thousand, six hundred forty".